Exchange Server 2010 Client Access Server Interview Questions

1.What is a Client Access Server in Exchange Server 2010?

Client Access server role in exchange server 2010 help all the exchange clients to access their mailbox. Exchange server clients like outlook, OWA, IMAP, POP3, Exchange Active Sync, ECP, Entourage clients will connect to client access server first and the request will be passed to respective mailbox server or mailbox database.

Addition features like auto discover and availability services are handled by client access server role.

2. What are the major changes in CAS in Exchange 2010, when compared with Exchange 2007?

When compared with client access server role in exchange server 2007, exchange server 2010 CAS server function as a MAPI end point for all the exchange clients by replacing the MAPI end point from mailbox server role to client access server role.

New high availability model for client access server introduced in exchange server 2010 named client access server array.

Exchange Control Panel is a new feature supported by client access server role, which will allow users having permission to manage certain tasks from client machine itself.

3. Name the new features introduced in Exchange 2010 CAS server?

Below are some the new feature introduced in client access server role on exchange server 2010.

RPC Client Access component that serves client request is now part of CAS server

• Client Access Server array high availability option for client access server


• Outlook web app feature like conversation view, search folders in OWA and owa mailbox policies etc


• Cross-site POP3 and IMAP4 client connectivity is supported by default in Exchange 2010

4. Explain client access Proxying and the supported clients?

Client Access server can act as a proxy for other Client Access servers within the organization by having single internet facing client access server. This is useful when multiple Client Access servers are present in different Active Directory sites in an organization and at least one of those sites isn't exposed to the Internet. Proxying will be supported by OWA, ECP and exchange active sync clients

5. Explain what are client access redirection and the supported clients?

Redirection is useful when a user connects to a Client Access server that isn't in their local Active Directory site or if a mailbox has moved between Active Directory sites. It's also useful if the user should be using a better URL, for example, one that's closer to the Active Directory site their mailbox resides in. Redirection will be supported by POP3 and IMAP4 clients.

6. What are the supportable clients available in exchange server 2010?

Exchange Server 2010 client access server supports, Outlook MAPI connection, OWA, ECP, IMAP4, POP3, Exchange Active Sync, entourage clients and EWS

7. Explain Exchange Active Sync in Exchange Server 2010?

Exchange ActiveSync enables mobile phone users to access their e-mail, calendar, contacts, and tasks and to continue to be able to access this information while they're working offline. The protocol, based on HTTP and XML, lets mobile phones access an organization's information on a server that's running Microsoft Exchange. Direct Push is the technology used in synchronizing emails to mobile devices

Feature like support for HTML messages, PIN reset, auto discover over air are the additional components inactive sync on exchange server 2010.

8. What you know about POP3 and IMAP client with exchange 2010?

POP3 is a client access method which uses outlook as the application to access the email from exchange server. If profile is configured using pop3, then allowing certain of emails to leave in server and rest of the emails will get download to the local machine. Email downloaded cannot be accessed anywhere from OWA etc

IMAP is also client access method to access emails, where the IMAP won’t download the emails locally. Exact sync of the emails and the folder structure in exchange server will be in sync when profile is configured in outlook IMAP4 configuration.

9. How outlook anywhere works in Exchange Server 2010?

Outlook Anywhere feature, formerly known as RPC over HTTP allow the exchange clients that use Outlook 2010, Outlook 2007, or Outlook 2003 connect to their Exchange servers from outside the corporate network or over the Internet using the RPC over HTTP Windows networking component.

The Windows RPC over HTTP Proxy component, which Outlook Anywhere clients use to connect, wraps remote procedure calls (RPCs) with an HTTP layer. This allows traffic to traverse network firewalls without requiring RPC ports to be opened. By default outlook anywhere is not enabled and it has to be manually enabled.

10. What are the new features in outlook web app?

Lot of new features are there in outlook web app and few are mentioned here

Outlook Web App Mailbox Policies, Conversion view, Chat, Attach message to messages and Standard version of OWA for all the web browsers.

OWA in exchange server 2010 is by default securely published using self signed certificate.

11. What is the function of availability service in exchange server 2010?

Exchange Server 2010 Availability service makes free/busy information available to Microsoft Office Outlook 2007 or 2010 and Outlook Web App clients. The Availability service improves information workers' calendaring and meeting scheduling experience by providing secure, consistent, and up-to-date free/busy information. By default, this service is installed with Exchange 2010

Outlook 2007 or 2010 and Outlook Web App use the Availability service to perform the following tasks:

• Retrieve current free/busy information for Exchange 2010 mailboxe


• Retrieve current free/busy information from other Exchange 2010 organization


• Retrieve published free/busy information from public folders for mailboxes on servers that have versions of Exchange earlier than Exchange 2010


• View attendee working hours


• Show meeting time suggestions

12. What are the services used by Client Access Server and inform their function?

Service related to client access server are IIS Admin, MSExchange Address Book Service, MSExchange AD topology, MSExchangeFDS, MSExchange Mailbox Replication, Protected Service host, exchange rpc, service host, W3svc, Winrm

13. Explain the auto discover functionality in exchange 2010?

Autodiscover is a new service in exchange server 2010 where it will automatically configure user profile settings for clients running Microsoft Office Outlook 2007 or Outlook 2010. Autodiscover uses a user's e-mail address and password to provide profile settings to Outlook 2007 or Outlook 2010 clients and supported mobile phones. If the Outlook client is joined to a domain, the user's domain account is used.

14. How the autodiscover service works in exchange server 2010?

When a Client Access server role installed on a computer, a default virtual directory named Autodiscover is created under the default Web site in Internet Information Services (IIS). This virtual directory handles Autodiscover service requests from Outlook 2007 or Outlook 2010 clients and supported mobile phone

Additionally, a new Active Directory object named the service connection point (SCP) is created on the server where you install the Client Access server role. The SCP object contains the authoritative list of Autodiscover service URLs for the forest.

When the client connects to Active Directory, the client looks for the SCP object created during Setup. In deployments that include multiple Client Access servers, an Autodiscover SCP object is created for each Client Access server. The SCP object contains the ServiceBindingInfo attribute with the fully qualified domain name (FQDN) of the Client Access server in the form https://CAS01/autodiscover/autodiscover.xml, where CAS01 is the FQDN for the Client Access server. Using the user credentials, the Outlook 2007 or Outlook 2010 client authenticates to Active Directory and searches for the Autodiscover SCP objects. After the client obtains and enumerates the instances of the Autodiscover service, the client connects to the first Client Access server in the enumerated list and obtains the profile information in the form of XML data that's needed to connect to the user's mailbox and available Exchange features

15. How Address book service helps the exchange 2010?

In earlier version of version of exchange, Exchange provided a referral service that told clients such as Outlook where they could find a server running the NSPI service. This referral usually pointed Outlook to a global catalog server. This has been redesigned in exchange server 2010, where the address book service in client access server will refer the request to global catalog server.

16. What is RPC client Access and inform its function?

In Microsoft Exchange Server 2007, the Client Access server role was introduced to handle incoming client connections to Exchange mailboxes. Although the majority of types of client connections were made to the Client Access server, Microsoft Office Outlook still connected directly to the Mailbox server when it was running internally with the MAPI protocol.

A new service was introduced with Exchange Server 2010 to allow these MAPI connections to be handled by the Client Access server. The RPC Client Access service provides data access through a single, common path of the Client Access server, with the exception of public folder requests, which are still made directly to the Mailbox server

17. Explain Client Access Array in short?

Client Access Array is a new feature in exchange server 2010, where it serves as a single contact point for all client connections within that Active Directory site. A Client Access server array can include one or many Client Access servers within a active directory site

18. What are steps to configure a CAS Array?

Steps involved in configuring the client access server array

• Create a Client Access array - New-ClientAccessArray -Name “Name” -Site “AD site Name” -fqdn “Name of the cas array (outlook.domainname.com). Once the cas array is created, create the address in DNS and associate it with the virtual IP address used for the Client Access array.


• Configure load balancing - Load balancing is recommended for high availability, failover, and for spreading the traffic load over multiple servers to help performance


• Configure RPC encryption settings


• Configure your Mailbox databases

19. Explain the virtual directories in CAS 2010 and what is the function of all those directories?

20. Users are not able to access OWA externally. How you will troubleshoot this?

If users are able to access OWA internally and externally not accessible then below troubleshooting steps can be followed

 Check whether OWA external url is mentioned on the properties OWA virtual directory in exchange management console

Check whether OWA is externally published

21. Unable to see the free busy information. Inform what you will do, if it is a single user issue and if it s for multi user issue?

If it is a single user issue - We can run the clean free busy switch, if still an issue, we can run the test email auto configuration to check whether the availability service url is properly resolving in outlook, if still an issue reconfigure the outlook profile

If it is a multi user issue - We can check the availability service is running on client access server or not, if it running and still an issue we can check whether IIS service is crashed etc. Check for event logs related to iis related issue, if everything is normal, we can go for restart of availability and IIS server in client access server

22. One user complaints that he is not able to set OOF in his outlook. He is getting error message like exchange server is unavailable. How you will troubleshoot?

We can check the below things

• Check whether the outlook profile is showing the oof url while doing test email auto configuration


• Check whether ssl certificate is still valid


• Check whether he can send oof from owa


• Reconfigure outlook profile etc

23. You are checking the client Access redirection functionality and it is not working. What you will do?

24. Can you inform a feature that is available in Outlook, which is not available in OWA?

25. Outlook 2003 clients are unable to connect to exchange 2010 mailbox. What will be the issue and how you will troubleshoot?

By default in RTM version of exchange server 2010, rpc client access encryption is enabled on mailbox database, when outlook 2003 user tries to connect exchange 2010 mailbox he will get an error. To avoid this encryption needs to be disabled on the mailbox database level.

26. You are not able to open a exchange server 2010 mailbox in outlook 2007 but you are able to access using OWA. It’s a new setup with 3 servers with CAS, mailbox and hub installed separately. How you will solve it?

May be the newly create user information may take some time to replicate across all the sites

We can check for whether MAPI mailbox feature is enabled on the mailbox properties

If hide from address is option is enable is checked, outlook profile cannot be configured, we can check that also.

27. What are the URLs provided to auto discover clients?

Below are the urls referenced to outlook clients when outlook profile is configured using auto discover

• Availability Service Url: https://servername.domainname.com/ews/exchange.asmx


• OOF Url: https://servername.domainname.com/ews/exchange.asmx


• OAB URL: Public Folder


• Unified Message Service Url: https://servername.domainname.com/unifiedMessaging/service.asmx


• Exchange Control Panel Url: https://servername.domainname.com/ecp

28. Newly created user account is not updating in GAL after one day. What are the troubleshooting steps you will follow?

If a user account is created newly it will take some time (6 hours to 24 hours) to replicate or update the new information in address book, if it is still unable to get the new information in address

I will check the event logs for any issue in online maintenance, if no issues then we can check the email address on the active directory general tab and the primary emails address on the mailbox properties are same. If it is not same new user account won’t appear.

29. Users on a particular database is facing problem in getting the OAB updated. What will be issue?

For the first attempt, I will check the issue in OWA; if user can see the address book properly then I will try to manually download the address book in outlook. If still an issue, Each and every mailbox database will be pointed to offline address book, need to check whether correct offline address is pointed. If it is pointed and still an issue, need to check whether public folder database is mounted.

30. Is it possible to add another site CAS server as a member of a CAS Array? Why not and when you can add other site member as a member of CAS Array?

When a Client Access server array is defined in an Active Directory site, it serves as a single contact point for all client connections within that Active Directory site. A Client Access server array can include one or many Client Access servers inside the active directory site. After a Client Access server array is defined within an Active Directory site, all Client Access servers within that Active Directory site are automatically part of the Client Access server array.

CAS array is bounded within an active directory site, and if we have two AD sites, we can create two CAS array one on each site.

31. User able set OOO in OWA but not in outlook. How you will help the user?

32. What are the things you will backup in Client Access Server?

As like mailbox server role, we need to keep a copy of client access server role configuration as a backup. Information like Internet Information Services (IIS) metabase data that a Client Access server uses to store Microsoft Office Outlook Web Access Virtual Directory configuration data, OWA url details, authentication settings can be taken as a note or MS released a script to take the CAS server configuration as backup.

33. Few of Outlook users are prompting for password again and again. What you will do?

Outlook password prompt issues can occurs, one miss configured exchange server environment

We change the auto discover configuration

We can the DNS configuration or the Domain controller and global catalog server assigned for the mailbox server role

We can check the permission assigned in IIS

We can check whether the local client computer is correctly configured with DNS settings

34. You are able to access OWA intermittently. If you refresh the OWA page, sometimes it will show the content, sometime it won’t. What will be issue?

It may be because of intermittent network connectivity issue. Need to check the internet connectivity or is the issue with IIS connectivity in client access server etc

35. How you will find a CAS server used by a user. We have 5 CAS servers; you have to inform a CAS server used by a user?

By default all the mailbox database will have a RPC Client Access Sever property on each mailbox database, it will be pointed to the client access server which is installed at first in exchange environment. We can find the mailbox database user and get the details from shell command

If we use the outlook test auto email configuration option, it will show the client access server which is used to configure the outlook profile in auto discover method

36. While accessing outlook, he is prompted with the certificate warning. How you will fix it?

By design, exchange server 2007 and 2010 will be assigned with the self signed certificate, where the outlook 2007 client ignore the certificate check and the outlook profile will be configured using autodisover. This is not the same with outlook 2010, it will check for cert and throw and error with certificate warning

We can install the certificate from owa to the trusted root container or we can install a valid SAN certificate for  all the services that are used by autodiscover in exchange server 2010.

37. Client Access Server has been crashed where a single CAS server is in place for the whole exchange environment. What will happen now?

All the exchange server clients connecting the exchange server mailbox will be disconnected. In exchange server 2010 including the MAPI connection, all the client connection go via client access server and if it goes down, all the client connection will be dropped.

Exchange Server 2010 Hub Transport Server Interview Questions

[notice]Please wait for answers which are all not answered here. If you want me to add any questions or answers, kindly leave your comments[/notice]

What is Hub Transport Server in Exchange Server 2010?

Hub Transport is the mail routing server that routes mail within the Exchange organization. Without having the Hub Transport Server the mail routing functionality won’t work in exchange server 2010. It handles all mail flow inside the organization, applies transport rules, applies journaling policies, and delivers messages to a recipient's mailbox. Messages that are sent to the Internet are relayed by the Hub Transport server to the Edge Transport server role that's deployed in the perimeter network.

What are the changes or new features in Hub Transport Server when compared with exchange server 2007?

Below are the new features available in exchange server 2010 related to Hub Transport server role

MailTips - MailTips provide extra information that's displayed to senders while they're composing e-mail messages.

Shadow redundancy - Messages that are submitted to an Exchange 2010 Hub Transport server are stored in the transport database until the next hop reports successful delivery of the message. If the next hop doesn't report successful delivery and it fails, the message is resubmitted for delivery.

Moderated transport - Exchange 2010 provides an approval workflow for sending messages to recipients. When you configure a recipient for moderation, all messages sent to that recipient must go through an approval process

End-to-end message tracking   Exchange 2010 transport provides users with the ability to track messages from submission to the final destination

Incremental EdgeSync - In Exchange 2010, the EdgeSync process has been changed to keep track of synchronized information and only synchronize the changes since the last replication cycle. This significantly reduces network traffic and greatly improves synchronization efficiency.

And other features like Transport Rule command improvements New and Set Transport Rule, The handling of distribution group expansion has improved in Exchange 2010. First, the amount of memory that's used for caching distribution group membership has been capped by a configurable limit and Message throttling improvements.

How the mail flow occurs in Hub Transport Server 2010?

Messages are submitted to the Hub Transport server in three ways: through SMTP submission, from the Pickup directory, or when a user inside the organization sends a message, which is picked up from the user's Outbox by the store driver. The store driver is a software component of the Hub Transport server that delivers inbound messages to Exchange stores, the databases that contain public folder and mailbox stores

When messages are submitted to the Hub Transport server, they're processed by the categorizer. The categorizer is a component of Exchange transport that processes all inbound messages and determines what to do with the messages based on information about the intended recipients. In Exchange 2010, the Hub Transport server uses the categorizer to expand distribution lists and to identify alternative recipients and forwarding addresses. After the categorizer retrieves full information about the recipients, it uses that information to apply policies, route the messages, and perform content conversion. Messages are then delivered locally by the store driver to a recipient's mailbox, or they're delivered remotely by using SMTP to send messages to another transport server. Messages that are sent by users in your organization are picked up from the sender's Outbox by the store driver and are put in the Submission queue on a server that runs the Hub Transport server role.

What are the queues available in Hub Transport Server 2010?

There are 5 mail queues available in Hub Transport Server; they are Submission queue, Mailbox delivery queue, remote delivery queue, Poison message queue, unreachable queue.

Explain Send Connector in Exchange Server 2010?

Send Connector represents a logical gateway through which outbound messages are sent. Exchange 2010 transport servers require Send connectors to deliver messages to the next hop on the way to their destination. A Send connector controls outbound connections from the sending server to the receiving server or destination e-mail system.

Send connectors that are created on Hub Transport servers are stored in Active Directory and are available to all Hub Transport servers in the organization. If a Send connector is configured to send messages to an external domain, any Hub Transport server in the organization will route a message for that domain to a source server for that connector to be relayed to the destination domain

Explain Receive Connector in Exchange Server 2010?

Receive connectors represent a logical gateway through which all inbound messages are received. It is require Receive connectors to receive messages from the Internet, from e-mail clients, and from other e-mail servers. By default, the Receive connectors that are required for internal mail flow are automatically created when the Hub Transport server role is installed.

By default two receive connectors will be created automatically with the name shown below, they are

Client Servername - This Receive connector accepts SMTP connections from all non-MAPI clients, such as POP and IMAP.

Default Servername - This Receive connector accepts connections from other Hub Transport servers and any Edge Transport servers you have.

Explain the dumpster changes in exchange server 2010?

Exchange Server 2007 introduced the transport dumpster feature for the Hub Transport server role. An Exchange 2007 Hub Transport server maintains a queue of messages delivered recently to recipients whose mailboxes are on a clustered mailbox server. When a failover is experienced, the clustered mailbox server automatically requests every Hub Transport server in the Active Directory site to resubmit mail from the transport dumpster queue. This prevents mail from being lost during the time taken for the cluster to fail over

Exchange Server 2010 introduces the shadow redundancy feature to provide redundancy for messages for the entire time they're in transit. The solution involves a technique similar to the transport dumpster. With shadow redundancy, the deletion of a message from the transport databases is delayed until the transport server verifies that all of the next hops for that message have completed delivery. If any of the next hops fail before reporting back successful delivery, the message is resubmitted for delivery to that next hop

Unable to send email to external domain, what are things you will check?

By default, when exchange server 2010 is installed with the default server roles, internal mail flow occurs and the external won’t. There is no send connector created to sending emails to external domain. Need to check the following

• Send connector to send emails to external domain needs to be created


• Exchange Server queues to be viewed to check whether the emails are stored in queue


• Check the smart host which is configured to relay the emails to external domain


• Any change on the ISP or the MX record configuration to b e checked

Unable to send email to one particular domain, what will be the issue? And how you will troubleshoot this issue?

If you are unable to send emails to particular domain, need to the following

Is the send connecter configured with * as the address space to send emails to external domain, if it is there then there is no need to create a separate connector for particular domain

Need to check the check the SMTP codes on the NDR received, based on the NDR we can troubleshoot further

What happened to routing group connector in Exchange Server 2010? Do we need Routing Group connector in Co existence environment with legacy version of exchange server?

Routing group and Routing group connector concepts are replaced with Active Directory site based email routing in exchange server 2010. If we are having a coexistence with legacy version of exchange server, automatically an routing group connector will be created to establish a mail flow between exchange 2010 and legacy version of exchange server

How to achieve High Availability of Hub Transport Server?

Deploying more than one Hub Transport server per site provides redundancy. When you install more than one Hub Transport server in an Active Directory site, the connections are distributed.

What needs to be back up in Hub Transport Server?  How to recover a Hub Server failure?

• Send connector configuration and the details are to be recorded\noted


• Receive connector configuration and the details are to be recorded\noted


• Need to have a detail record on the accepted domain and relay domain configured

If the server gets crashed,

• We can rebuild a server with the same computer name and IP address configuration,


• Apply the same service pack and patches as like before


• Recover the server using recover switch, this needs to performed at the command line installation

Explain a back pressure? When it will occur and what will happen? How to solve this?

Back pressure is a system resource monitoring feature of Microsoft Exchange Transport service that exists on Microsoft Exchange Server 2010 Hub Transport and Edge Transport servers. Exchange transport can detect when vital resources, such as available hard disk space and memory, are under pressure, and take action in an attempt to prevent service unavailability.

When back pressure occurred and the level is

Normal - Server accepts new connections and messages

Medium - Mail from senders in the authoritative domain can flow and the other message will be queued

High - Full back pressure is applied. All message flow stops, and the server rejects all new incoming MAIL FROM commands.

To solve this issue, we need to make sure the disk space on the queues and queue database disk are having enough disk space and the hub transport server is having enough memory.

What is an Accepted Domain? What is the use of it?

An accepted domain is any SMTP namespace for which a Microsoft Exchange organization sends or receives e-mail. Accepted domains include those domains for which the Exchange organization is authoritative and responsible to receive emails for those accepted domains.

If we look at the use of accepted domain, if company have additional domain names and they cannot setup exchange server for each and every domain names, they can create accepted domain and point the MX record to their exchange domain. Also by creating a new email address policy they can easily change the email address for all users in exchange organization.

What is the use of remote domain?

Remote Domains can be configured to change the settings for message transfer between the Microsoft Exchange Server 2010 organization and domains outside your Active Directory forest. When you create a remote domain entry, you control the types of messages that are sent to that domain. You can also apply message format policies and acceptable character sets for messages that are sent from users in your organization to the remote domain.

Explain Relay Domain?

Relay domain will allow the exchange server to receive a email for other exchange domain and it will be forwarded to the relay domain

Two types of relay domain are available internal relay domain and external relay domain.

What is the use of Pick up and Replay directory? How to secure messages in those directories?

How shadow redundancy helps in mail flow?

Shadow redundancy provides the following benefits:

• It eliminates the reliance on the state of any specific Hub Transport or Edge Transport server. As long as redundant message paths exist in your routing topology, any transport server becomes disposable.


• If a transport server fails, you can remove it from production without emptying its queues or losing messages.


• If you want to upgrade a Hub Transport or Edge Transport server, you can bring that server offline at any time without the risk of losing messages.


• It eliminates the need for storage hardware redundancy for transport servers.


• It consumes less bandwidth than creating duplicate copies of messages on multiple servers. The only additional network traffic generated with shadow redundancy is the exchange of discard status between transport servers. Discard status is the information each transport server maintains. It indicates when a message is ready to be discarded from the transport database.


• It provides resilience and simplifies recovery from a transport server failure

What will happen if the queue database gets corrupt? How you will recover that?

Why the queue database extension mention as .que file?

What is priority queuing in exchange server 2010?

How you will configure the mail flow between edge and hub transport server?

Requirement is to configure the external mail flow happen only through a particular site, how you will achieve this?

Queues are filling on Submission queue, what are the things you will check? All the stores are mounted and the exchange server related services are running normal here.

How to force the mail from queue, we don’t have option like exchange server 2003 queue viewer?

How the mails the secured in exchange server? What kind of secure communication will occur between server to server mail flow and server to client mail flow?

Single Mailbox is creating bulk number of email which leads to bulk number of log file creation, how you will find the mailbox and how you will fix the issue?