In Microsoft Office Outlook 2007, you cannot suppress the Autodiscover redirect warning for HTTP and SRV redirections. The Autodiscover redirect warning is as follows:
Allow this website to configure firstname.lastname@example.org server settings? https://mail.hosting.com/autodiscover/autodiscover.xml Your account was redirected to this website for settings. You should only allow settings from sources you know and trust.
When this warning message occurs, you may choose not to be asked about the specific website again.
You or administrators may want to suppress the initial warning message for a specific HTTP redirection that is expected in your organization. This article contains information about how to do this.
For more information, click the following article number to view the article in the Microsoft Knowledge Base:
940881 A new feature is available that enables Outlook 2007 to use DNS Service Location (SRV) records to locate the Exchange Autodiscover service
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 Windows
To enable this hotfix, follow these steps:
Close Outlook 2007.
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.
Locate and then click to select the following registry subkey:
On the Edit menu, point to New, and then click String Value.
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:
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.
To add additional HTTPS servers to which AutoDiscover can be redirected without displaying a warning, repeat steps 4 and 5 for each server.
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: