Hi,
I have been struggling with this for months now. I get Event ID 24 with this error before every backup. I can't find any reason for it. I have WSB running on Server 2012 R2 with hyper-v only, backing up 2 VMs to 2 locally attached USB drives, which are swapped out weekly.
Backup started a fresh backup for volume '{00000000-0000-0000-0000-000000000000}' ('Esp') :
[Reason: 'Volume size changed']. This may cause loss of older backup versions when backup completes.
Some people have suggested that it is down to lack of space on the destination drives, but i have formatted the drives and started again. The drives are 2TB and the total backup size is ~750gb. Even though the message suggests we will lose old backups there about 8 available to restore.
I could really do with some help getting this resolved. If not, at least some pointers as to which the volume is with all the zeros.
Thanks