Hello Steve,
thanks first for sour detailed answer.
I have checked all things you mentioned before. But that didn't help. What I tried yesterday was to run the jobs after a reboot of the Backup Server. The ran fine. The next scheduled jobs again ran with the described problems.
We have two Exchange Server and both jobs have the same problem.
I'll try to backup each store separate and will post the results here.
If you have any news on that, I would be glad to hear from you.
Currently we are doing only Full Backups...
I have misgivings that as in earlier Versions we will have similar problems...: Something does not work, then it does.. then again not... noone knows where the problem is.
Thanks so far.