VMware Backup fails with Could not find virtual machine specified (80236)

Date: OCT 2010
Product & Version: Vmware all versions
OS Version: all
Application version: ESX 3.5


Symptoms:
Second virtual machine backup fails with "Could not find virtual machine specified," and we see the following in the binary log below.

From binary log:
Information 2010/10/15 01:47:09 644 Data Plugin HRFVCB1 [2010-10-15 01:47:08.805 'vcbMounter' 228 error] Error: Could not find virtual machine specified by ...
Sub text:
[2010-10-15 01:47:08.805 'vcbMounter' 228 error] Error: Could not find virtual machine specified by uuid:50197d3b-7f4f-a5e8-d1f6-5e7e0878cf04

From binary log:
Warning 2010/10/15 01:47:10 644 Data Plugin HRFVCB1 Failed with exit code 1
Error 2010/10/15 01:47:10 644 Data Plugin HRFVCB1 Failed to backup VM F1-VTAG2


When a backup of the virtual machine is run on its own, the backup works.


Cause:
VM has been deleted or corrupted backup selection set in schedule database.

Using vSphere verify the VM does exist.

If it does not exist, the backup failure is normal and we can't snapshot/backup a missing VM.

If the VM does exist, then check then try creating a new new backup selection set and delete old backup job.