Microsoft Hyper-V • Failed to preprocess target Error: The given key was not present in the dictionary

Case # 07693387

Hi guys,

We have started getting this error almost 7 days ago, on Thursday night last week:

1/05/2025 10:49:43 pm :: Failed to pre-process the job Error: Cannot find full backup
1/05/2025 10:49:43 pm :: Failed to perform post-processing: Cannot find full backup

I unplugged the drive and reconnected it, which then gave this error instead:

2/05/2025 10:25:11 pm :: Failed to pre-process the job Error: The given key was not present in the dictionary.
2/05/2025 10:25:11 pm :: Failed to preprocess target Error: The given key was not present in the dictionary.

I then deleted all the backups and restarted it, which did the backup, but then started saying this again:

5/05/2025 10:39:20 pm :: Failed to pre-process the job Error: Cannot find full backup
5/05/2025 10:39:20 pm :: Failed to preprocess target Error: Cannot find full backup

I changed the backup drive with the next one and it has gone back to a previous error:

7/05/2025 1:30:43 pm :: Failed to pre-process the job Error: The given key was not present in the dictionary.
7/05/2025 1:30:43 pm :: Failed to preprocess target Error: The given key was not present in the dictionary.

I have never seen this error before, and I'm not sure what it is referring to? Something in the database? I have opened the ticket mentioned at the top.

Statistics: Posted by AlexLeadingEdge — May 07, 2025 2:15 am

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