Errors trying to covert VM?

I'm trying to use Vmware Converter Standalone 6.0.0 build 2716716 to convert a VM on an ESX6 server.  it worked perfectly fine in the past.  All of a sudden I'm getting an error at the very end of the conversion:

FAILED: An error occurred during the conversion:

'The session does not have the required permissions'

and in the log highlights:

Error: Unable to clone disk [DATASTORENAME] path/vmname.vmdk on the virtual machine 'Vm Name'.

Any idea?  I did recently install Veeam backup & replication on the same client machine Converter is running on.  Veeam runs fine.

Thanks for any help.