I found the following Error on the BARS logfile:
[02:29:30 AM] Copying Lmhosts and hosts file to stage directory.
[02:29:30 AM] Error: File Lmhosts not found in source folder.
[02:29:30 AM] Staging hosts file.
[02:29:30 AM] Failed to stage hosts File.
I got this error three time for the 3 IVRs im backing up. Althought at the end he says : Archive built successfully.