Error encountered with NTI Shadow

Hi,
I am using a Mac for processing of thousands of my images. I just got an HP Media Vault MV2010 to backup these images together with old backup software, NTI Shadow. But when I started the backup process, I got this error message, see below. I have checked the connection of the storage to the PC and it seemed connected fine.
I restarted the backup process but I still encountered the same error message. I got no answers from the websites so I turned to this forum to ask for advices.
Please help!

NTI Shadow
Communication to the HP Media Vault has been lost. Tour file/folder changes will not be backed up.
Check the connections, make sure the HP Media Vault is on, and restart your backup job.
