In some cases when you are trying to perform multiple actions at the same time (sessions), you may face the following error:
“Max number of PowerShell sessions exceeded. Please wait for other jobs to finish and try again later”
There is a limitation on the maximum number of sessions. The current maximum number of sessions is by design limited to 3.
The actions that use PowerShell sessions are:
- Get-List (for User Mailboxes, Distribution Lists, Shared Mailboxes, Rooms & Equipment)
- Preprocessing (for User Mailboxes, Distribution Lists, Shared Mailboxes, Rooms & Equipment)
- Permission migration
- GalSync Push.
Resolution of the PowerShell sessions limitation
The only way to get rid of this error is to wait for a session to complete or stop one and retry.