Platform: Source: All Destination: Microsoft 365
Problem
When migrating to Microsoft 365 the following error is seen:
Migration failed: InvalidUser
Solution
This error indicates that the specified user does not exist in the target Exchange system, and auto discovery failed. You should ensure that the specified Import Name matches the SMTP address of the user(s) in the target system.
This can also happen if the user mailbox has not yet been fully provisioned. This can occur shortly after user creation before all the backend processes have been completed. If you are sure the users exists and are getting this error, wait a while and try the migration again