You cannot suppress the Autodiscover redirect warning in Outlook 2007

How to enable the hotfix

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:

322756 How to back up and restore the registry in WindowsTo enable this hotfix, follow these steps:

1. Close Outlook 2007.
   

2. Start Registry Editor.

   • In Windows Vista, click Start , type regedit in the Start Search box, and then press ENTER.
     
       If you are prompted for an administrator password or for confirmation, type the password, or click Continue.

   • In Windows XP, click Start, click Run, type regedit in the Open box, and then click OK.
     

3. Locate and then click to select the following registry subkey:
   

   HKEY_CURRENT_USER\Software\Microsoft\Office\12.0\Outlook\AutoDiscover\RedirectServersNote You can also use the following registry subkey:

   HKEY_CURRENT_USER\Software\Policies\Microsoft\Office\12.0\Outlook\AutoDiscover\RedirectServers

4. On the Edit menu, point to New, and then click String Value.
   

5. Type the name of the HTTPS server to which AutoDiscover can be redirected without prompting for confirmation from the user, and then press ENTER. For example, to allow redirection to https://adatum.com, the first String Value (REG_SZ) name would be this:
   
   

   adatum.com
   Note There is no need to add text to the Value data box. The Data column should remain empty for the string values that you create.

6. To add additional HTTPS servers to which AutoDiscover can be redirected without displaying a warning, repeat steps 4 and 5 for each server.

7. On the File menu, click Exit to exit Registry Editor.

Note Before the October 26, 2010 hotfix update, Outlook 2007 used a different registry path and value:

Key: HKEY_CURRENT_USER\Software\Microsoft\Office\12.0\Outlook\AutoDiscover

or

Key: HKEY_CURRENT_USER\Software\Policies\Microsoft\Office\12.0\Outlook\AutoDiscover

Name: RedirectServers

Type: REG_SZ (string)

Data: adatum.com; contoso.comAfter installing any current hotfix update that is later than the October 26, 2010, hotfix update for Outlook 2007, this registry key and value is no longer used.