You can choose to "Retain" the desired backup set. Have a look at this KB article on how to do so -https://www.veritas.com/support/en_US/article.000108634
Does the backup proceed if backing up directly via the ESXi host and not the vCenter ?If no, then have you tried testing with different VMs or do the backup go queued irrespective of the VMs being backed up ?
Is it possible to test with another server running an OS such as Win 2008 R2 ?Also, logging a support case with us should help for us to troubleshoot this error in detail. Thanks.