As discussed on another topic, i have created a new topic here for this problem.
More info over this topic: https://forum.acronis.com/forum/acronis-backup-vmware-version-9-forum/disk-full
To reply on the questions,
1. the failing job does not conain other vm's on the same host.
2. the failing job never succeeded his first backup
3. taking a snapshot in vmware works without problems.
Can someone help me please?