I've got a Synology NAS here and a few months ago I sadly got the message, something like
Time Machine backup is corrupt and therefor has to start a new backup.
However, as my NAS is starting to get more and more filled, I'm seeking to kill some data. I found this old backup which is about 650GB of size.
And my only question is: Can it be of any use or should I just remove it completely?
If you ask "But by starting a new backup, the old one gets deleted. Why do you still have it?" That's because it ended up in the Trash, instead of permanently deleted.