When using the SRV autodiscover method, you may get this warning when Outlook is started up:
“Your account was redirected to this website for settings. You should only allow settings from sources you know and trust.”
This will pop up every time that Outlook opens and periodically while Outlook is running. This is because Outlook has found our autodiscover SRV record that is configured for the email domain litwareinc.com. In this case, the SRV record is _autodiscover._tcp.litwareinc.com. For more information about configuring SRV records for autodiscover, see here.
The server we have configured in the SRV record is mail.litwareinc.com and this is the same server we can see in the notification above.
The warning is expected and can be safely ignored or suppressed. To suppress the error, we need to add a registry value in each user’s registry.
First, open up regedit then browse to the RedirectServers subkey using the path relevant to the version of Outlook you’re using:
As you can see, by default there are entries for autodiscover.hotmail.com and autodiscover-s.outlook.com.
Next, right click and create a new string value with the name of the server we are redirecting to in the SRV record, in our case this is mail.litwareinc.com.
Once done, you should no longer be prompted with this warning.
Ok, that’s great but what happens if you have a few thousand machines across the business that need this change. In that case, you can make the changes above then export the RedirectServers registry subkey to a .reg file then deploy it in a user logon script or using Group Policy Preferences.
To use a logon script, add this line to the script where \\server\share\RedirectServers.reg is the path to your exported registry key:
regedit.exe /s \\server\share\RedirectServers.reg
If you want to use Group Policy Preferences then create a new Group Policy Object and link it to your user OU. Once done, browse to User Configuration\Preferences\Windows Settings\Registry and create a new registry item with the below settings:
Key Path: Software\Microsoft\Office\15.0\Outlook\AutoDiscover\RedirectServers
Value name: mail.litwareinc.com
Value type: REG_SZ
You’re now able to deploy your fix.