Backup has SUCCEEDED with WARNING: Change Block Tracking could not be reset, causing full backup: Second attempt failed.

Hi,

Something strange here. Networker 9.1 with vProxy and only CBT backup, no NBD. All backups are succeeded. A few backups have the following warning: "Backup has SUCCEEDED with WARNING: Change Block Tracking could not be reset, causing full backup: Second attempt failed." This results in a longer backup windows because these vm's are fully backupped everytime.

The vm's have no other snapshots and virtual hardware is version 8 and newer. So incremental backup is supported?

Can't find the root cause. Someone any idea?

Cheers!

Vincent