This error message usually reveals a corruption or a inconsistency in the data being managed by amManager.
In order to get rid of this wrong cached data, please proceed as follows:
Open a DOS command prompt window with elevation (as Administrator).
Stop the amManager by running the command:
caf stop ammanager
and verify it is actually stopped by running:
You can also check in Task Manager that amManager (process amObjectManager.exe) is not running:
After that, restart amManager by running:
caf start ammanager
And verify it is actually running with the command:
You can now check in Task Manager that amManager (process amObjectManager.exe) is running:
The status of the job should be correctly retrieved now.