we are doing a cross forest Migration , we are using the Quest AD And EX tool for the migration after Switching the Mailbox from source to Target  its says Switch Completed and then we are running CPUU -update utility , we see in the logs saying The switch message was not found. and says unable to connect to the source auto discover. when we try to open the migrated mailbox using owa it works fine but not trough outlook.

Summary: 1 profile(s) were processed.
4/7/2020 10:50:13 AM 1408   [Info]        Profile 'Outlook': Profile cannot be resolved and is being skipped.
4/7/2020 10:50:13 AM 1408   [Trace]   Restore properties of the registry key 'Software\Microsoft\Office\15.0\Common\Identity'.

do we have recommendations to follow to checks where it is fails to switch the outlook profile. 

  • You are really going to need to open a support case for this as there is really no way anyone will be able to help from those two lines from the logs. My best guess to resolve this would be to set Autodiscover URLs in the CPUU configuration. Select Manually configure Autodiscover service URLs and enter a source and target Autodiscover service URL. This will remove the DNS discovery process and tell CPUU exactly where to go.