Event ID : 4001 A transient failure has occurred. The problem may resolve itself in awhile. The service will retry in 56 seconds.

1. Check out the database where is the location of Microsoft System Attendant; Use the below command;
Get-MailboxStatistics | Where-Object {$_.DisplayName -eq "Microsoft System Attendant"} | fl
2. Make sure the database is mounted.
*for my lovely Chubby*