Event IDs 157 and 58 while Backup is running

[Daniel_Be_]

Hello,

while the Backup is running we're getting the the folliwing error messages in the eventlog:

Are these errors produced by Backup Exec?

[VJware]

Are these errors received when you backup VMs ? If yes, are you using VMware or Hyper-V hosts ?

[Daniel_Be_]

Yes, this warning is received during the backup.

We are using VMware.