Cannot Stop Running Backups

I also occasionally have this problem of a task hanging at 100%. Here's what I do to cancel the task:

1. Exit ABR 10.
2. Reboot, or run services.msc and restart all Acronis services.
3. Run C:\Program Files (x86)\Acronis\BackupAndRecovery\schedmgr.exe and issue the "task zap" command. This will deleted all scheduled tasks on the machine. Exit schedmgr.exe.
4. Delete all files you find in the following folders:
- C:\ProgramData\Acronis\BackupAndRecovery\MMS\Policies\
- C:\ProgramData\Acronis\BackupAndRecovery\MMS\PolicyStatistics\
- C:\ProgramData\Acronis\BackupAndRecovery\MMS\TasksStorage\

When you run ABR 10, you should see that there are no running tasks, that the backup plan has been deleted, and you will have to recreate it.

Had a job freeze using ABR 11, but wasn't keen on following any approach as suggested above involving the deletion of a backup plan.

Followed up with Acronis support for a solution that seems to work well and is quite simple: remove the affected machine from AMS and the stuck job will disappear. You can then add the machine to AMS again (the machine has to be on the network to add it, in my case it was a laptop that had been shutdown while validation was running).

Hmm - I got the same suggestion but had to edit all backupplans after this since the machine references were changed.
After this support provided a SQL script to delete "zombie" tasks.

SOLVED: Deleted and re-added the machines in the Acronis Management Server twice.

Management Server and Agents are Acronis Backup and Recovery 10, Version 10.0.12457. (I will eventually be upgrading, but for now just trying to get all backups working right on all the machines). I have three tasks that show as running on the management server at 0% and I cannot stop, delete or edit them. I click stop and it processes for a few seconds but the task doesn't show as stopped. I tried deleting the backup policies and re-adding them, tried the task zap on the local machines and tried to delete the log files as well. I also deleted and re-added the machines via AMS. The funny thing is that the tasks do not show up in the Backup Plans and tasks section when I connect directly to the machine, they only show up on the management server in the Tasks section. We had to rebuild the management server recently due to a system issue, so I know that is the source of these running tasks from months ago. Any idea on if the "After this support provided a SQL script to delete "zombie" tasks." would work in this case as referenced by Endurance?
Thanks in advance!