Office365 migration – Outlook autodiscovers internal Exchange server

During a cutover migration you will usually end up with the on-premises Exchange server (as part of SBS for example) still running and this can cause issues whilst trying to get Outlook clients to autodiscover the Office365 servers.

The first thing to do is to remove the Autodiscover Virtual Directory:

Open an (elevated) command prompt window and back up the IIS configuration:

%windir%\system32\inetsrv\app\cmd.exe add backup “Before Removing Autodiscover”

Open an (elevated) Exchange Management Shell and identify the current autodiscover virtual directory:

Get-AutodiscoverVirtualDirectory | fl Name, Server, InternalUrl, Identity

Make a note of, or copy the Identity value (e.g. “SBSERVERautodiscover (SBS Web Applications)”) to the clipboard.

Remove-AutodiscoverVirtualDirectory -Identity “<Identity>”

You will have to confirm by typing a “Y”.

Check that the autodiscover virtual directory is gone:

Get-AutodiscoverVirtualDirectory | fl Name, Server, InternalUrl, Identity

This should now return nothing.

If you find that Outlook still finds the local Exchange server, then browse to the following reg key on the PC when logged in as the user:

HKEY_CURRENT_USER\Software\Policies\Microsoft\Office\15.0\Outlook\Autodiscover

add the following item (type DWORD):

ExcludeScpLookup and set the value to 1.