Our Differential backups will succeed one night and then fail the next. We suspect it is either related to the following logs
Every day at 7:19 we get this sequence of events in the log for each database we have in SQL Server
I/O is frozen on database DATABASENAME No user action is required. However, if I/O is not resumed promptly, you could cancel the backup.
I/O was resumed on database DATABASENAME No user action is required.
Database backed up. Database: DATABASENAME, creation date(time): 2010/11/04(23:28:04), pages dumped: 841, first LSN: 35:483:37, last LSN: 35:499:1, number of dump devices: 1, device information: (FILE=1, TYPE=VIRTUAL_DEVICE: {'{F8C10393-542B-4491-8135-BE0545F42EBE}22'}). This is an informational message only. No user action is required.
OR
that related to our online backup software Mozy.
Any ideas?