Backup Failing with "Unknown algorithm 'TransformForeverIncremental'"
I have a weekly backup that I wanted to run with forward incrementals forever, so I created it with 100 backups. Well, 100 isn't forever, so a couple weeks ago, it started rolling older backups into the original full backup. I was copying the new full backup to another drive and the system happened to run another backup at that same time, so it tried to roll the oldest backup into the file I was copying, but since I had it locked, the merge failed.
Now, when I try to run the backup again, I get the message below. I only found one reference to that error message and it was from 2016. Any thoughts on how I can get this backup chain functional again? I'm sure I can run a new Active Full, but I'd rather not because of the size. The new incremental seems to have been created OK, it's just the merge that failed. I'm not sure whether the backup chain is even useful for a restore at this point.
Error: Failed to repair VM 'VMNAME' in backup '9/30/2024 11:03:42 PM'. Unknown algorithm 'TransformForeverIncremental'