Incremental image backups failed : Error opening previous client bitmap

Hello,

We’ve got few clients having this message under /var/log/urbackup.log when doing incremental image backup, even after doing a fresh full image backup just before :

2022-01-27 05:42:45: ERROR: Request of image backup failed. Reason: Error opening previous client bitmap

Full image backup works correctly.

Any ideas ?

Best regards,

Config : Debian 10 / Urbackup Server 2.4.13 / Urbackup client 2.4.12-cbt / vhdz backend