When you use Outlook with an Exchange 2007 mailbox, you cannot connect to Exchange 2007, and you receive an error message

When you start Outlook and you use a profile for a Microsoft Exchange Server 2007 mailbox, you cannot connect to Exchange 2007, and you receive the following error message: Or

This behavior occurs when one or more of the following conditions are true:

• You do not have an existing public folder tree.
• MAPI is disabled for your mailbox.
• Encryption is required for the Exchange connection.
• Cached Exchange Mode is required for your mailbox.
• RPC/HTTP mode is disabled for your mailbox.
• Your version of Outlook is specifically blocked by Exchange 2007.

To resolve this behavior, use one or more of the following methods, as appropriate for your situation.

Note You may need to restart the information store to apply any changes in any of the methods listed below.

Method 1: Create an Exchange 2007 public folder tree

If you do not have an existing public folder tree and you are trying to connect with a Microsoft Office Outlook 2003 or earlier client, you cannot access an Exchange 2007 mailbox. This problem may occur when you delete the last existing public folder store.

Create an Exchange 2007 public folder store. To do this, follow these steps:

1. Click Start, click All Programs, click Microsoft Exchange Server 2007, and then click Exchange Management Console.
2. Expand Server Configuration, and then click Mailbox.
3. Right-click the storage group that you want to modify, and then click New Public Folder Database.
4. Create the public folder database by using the New Public Folder Database wizard.

If you are using an Outlook 2003 client or an earlier verison of an Outlook client, you must restart the Microsoft Exchange Information Store service before you can connect to Exchange 2007.

Method 2: Enable MAPI for your mailbox or use a different method to connect to Exchange 2007

Determine whether MAPI is disabled for your mailbox. To do this, follow these steps:

1. Click Start, click All Programs, click Microsoft Exchange Server 2007, and then click Exchange Management Shell.
2. Type the following command, and then press ENTER:
   Get-CasMailbox MailboxName | FL mapienabled
   If this command returns False, MAPI is disabled for your mailbox.

If MAPI is disabled for your mailbox, use one of the following methods:

• Enable MAPI for your mailbox. To enable MAPI for your mailbox, follow these steps:
  1. Click Start, click All Programs, click Microsoft Exchange Server 2007, and then click Exchange Management Shell.
  2. Type the following command, and then press ENTER:
     Set-CasMailbox MailboxName -mapienabled:$true
• Connect to Exchange 2007 by using one of the following methods:
  • Create an e-mail account in Outlook that uses the Post Office Protocol (POP 3) server type.
  • Create an e-mail account in Outlook that uses the Internet Message Access Protocol (IMAP) server type.
  • Use the Outlook Web Access (OWA) Web client.

Method 3: Enable encryption for the Exchange 2007 connection

1. Determine whether an encrypted connection is required for your mailbox. To do this, follow these steps:
   1. Click Start, click All Programs, click Microsoft Exchange Server 2007, and then click Exchange Management Shell.
   2. Type the following command, and then press ENTER:
      Get-MailboxServer ServerName | FL MAPIEncryptionRequired
      If this command returns True, you must connect to Exchange 2007 by using an encrypted profile.
2. Enable encryption for the Exchange 2007 connection. To do this, follow these steps:
   1. Click Start, click Run, type control, and then click OK.
   2. Double-click Mail, and then click Show Profiles.
   3. Select your profile, and then click Properties.
   4. Click E-mail Accounts, select View or Change Existing E-mail Accounts, and then click Next.
   5. Select the Exchange account, and then click Change.
   6. Click More Settings, and then click the Security tab.
   7. Click to select the Encrypt data between Microsoft Office Outlook and Microsoft Exchange Server check box.
   8. Click OK, click Next, click Finish, and then click Close.

Method 4: Enable Cached Exchange Mode for your mailbox, or disable the requirement for your mailbox to use Cached Exchange Mode

1. Determine whether Cached Exchange Mode is required for your mailbox. To do this, follow these steps:
   1. Click Start, click All Programs, click Microsoft Exchange Server 2007, and then click Exchange Management Shell.
   2. Type the following command, and then press ENTER:
      Get-CasMailbox MailboxName | FL MAPIBlockOutlookNonCachedMode
      If this command returns True, you must connect to Exchange 2007 by using Cached Exchange Mode.
2. Enable Cached Exchange Mode for your mailbox, or disable the requirement for a mailbox to connect to Exchange 2007 by using Cached Exchange Mode.
   • Enable Cached Exchange Mode for your mailbox. To do this, follow these steps:
     1. Click Start, click Run, type control, and then click OK.
     2. Double-click Mail, and then click Show Profiles.
     3. Select your profile, and then click Properties.
     4. Click E-mail Accounts, select View or Change Existing E-mail Accounts, and then click Next.
     5. Select the Exchange account, and then click Change.
     6. Click to select the Use Cached Exchange Mode check box.
     7. Click Next, click Finish, and then click Close.
   • Disable the requirement for a mailbox to connect to Exchange 2007 by using Cached Exchange Mode. To do this, follow these steps:
     1. Click Start, click All Programs, click Microsoft Exchange Server 2007, and then click Exchange Management Shell.
     2. Type the following command, and then press ENTER:
        Set-CasMailbox MailboxName -MAPIBlockOutlookNonCachedMode:$false

Method 5: Enable RPC/HTTP mode for your mailbox

1. Determine whether RPC/HTTP mode is disabled for your mailbox. To do this, follow these steps:
   1. Click Start, click All Programs, click Microsoft Exchange Server 2007, and then click Exchange Management Shell.
   2. Type the following command, and then press ENTER:
      Get-CasMailbox MailboxName | FL MAPIBlockOutlookRpcHttp
      If this command returns True, you cannot connect to Exchange 2007 by using RPC/HTTP.
2. Enable RPC/HTTP mode for your mailbox. To do this, follow these steps:
   1. Click Start, click All Programs, click Microsoft Exchange Server 2007, and then click Exchange Management Shell.
   2. Type the following command, and then press ENTER:
      Set-CasMailbox MailboxName -MAPIBlockOutlookRpcHttp:$false

Method 6: Unblock your version of Outlook in Exchange 2007

Important This section, method, or task contains steps that tell you how to modify the registry. However, serious problems might occur if you modify the registry incorrectly. Therefore, make sure that you follow these steps carefully. For added protection, back up the registry before you modify it. Then, you can restore the registry if a problem occurs. For more information about how to back up and restore the registry, click the following article number to view the article in the Microsoft Knowledge Base:

A version of Outlook can be blocked in Exchange 2007 in one of the following two ways:

• A version of Outlook can be blocked by modifying the registry. For more information about how a version of Outlook is blocked by using the registry, click the following article number to view the article in the Microsoft Knowledge Base:
  288894 How to disable MAPI client access to a computer that is running Exchange Server
  To unblock a version of Outlook by using the registry, you can modify or remove the registry data that is described in this Knowledge Base article.
• A version of Outlook can be blocked for a mailbox by using an Exchange Management Shell command that resembles the following command:
  Set-CasMailbox <MailboxName> -MAPIBlockOutlookVersions:"-11.8010.8036"
  This command blocks any version of Outlook that is earlier (previous) than 11.8010.8036.
  
  
  Set-CasMailbox <MailboxName> -MAPIBlockOutlookVersions:"11.8010.8036-"
  
  
  This command blocks any version of Outlook that is later (older) than 11.8010.8036.
  
  
  To determine what version of Outlook is connecting to Exchange 2007 you can do one of the following.
  • Download and run ExMon from the following Web site:
    http://www.microsoft.com/downloads/details.aspx?displaylang=en&FamilyID=9a49c22e-e0c7-4b7c-acef-729d48af7bc9
  • Use an Exchange 2007 Management Shell command:
    To do this, follow these steps:
    1. Click Start, click All Programs, click Microsoft Exchange Server 2007, and then click Exchange Management Shell.
    2. Type the following command, and then press ENTER:

       Get-LogonStatistics <MailboxName> | FL*client*

    Note When you see the build number it will look something like this. "11.0.8010.8036"
    You will need to truncate the 0 so that is looks like this "11.8010.8036"
  To unblock a version of Outlook for a mailbox in Exchange 2007, use an Exchange Management Shell command. To do this, follow these steps:
  1. Click Start, click All Programs, click Microsoft Exchange Server 2007, and then click Exchange Management Shell.
  2. Type the following command, and then press ENTER:
     Set-CasMailbox MailboxName -MAPIBlockOutlookVersions:$null