To cancel a running task on PowerShell you can use Task Manager or the Windows Console.
Note: In both cases, ShareGate Migrate does not undo what has already been migrated.
How-to
Task Manager
To cancel a running task using Task Manager:
Select Ctrl+Alt+Delete simultaneously to open Windows Task Manager.
Select Windows PowerShell from the list.
Click End Task. This will close PowerShell and kill the running task.
Note: The task may still appear to be running on ShareGate Migrate even though it has ended; this is normal behavior. You may need to restart the application for the task to appear as cancelled.
Windows Console
To cancel a running task using the Windows Console:
Select Ctrl+C.
After a delay, the task will end.