Error opening the snapshot disks using given transport mode: Status 23

Hello All,

We recently moved the vmware from windows to an appliance post which i see the vm backups failing with error 23 which was working before. I see that the connectivity is fine between the backup host(mediaserver and windows OS) and the vmware. We are using both SAN and nbd as transport modes. I could see on the Vcenter that  the snapshot i created and then removed immediatly. I am sure this is a connectivity issue between the baskup host and the vmware data stores, could some one help me resolve this. This is an isolated environment and I handle all of the servers, so i take care of this windows media server as well. please let me know if you need any logs.

Netbackup 7.5.0.6, Vmware 6.5, Master:Solaris, Media:Windows 2008 R2

Thank you in advance.