Exchange 2003 restores failing with error 5

[st0kes]

Here's the problem I've got. I have set up a disaster recovery server with Exchange 2003 installed, I have installed netbackup client 4.5.

I have been able to do 2 successful restores to this box from Netbackup but since then every restore fails with error 5, and every time I log on I get a windows error that Netbackup has encountered an error and needs to close.

I've tried reinstalling the netbackup client but it makes no difference. There are no problems with the network connection to this box, the wins/dns all check out OK, it can ping/be pinged from the netbackup server console.

I had the same problem on another exchange box a month ago but that box was rebuilt and Netbackup restores are now working .. which makes me think it's a client issue on my DR box, can anyone give me any clues/pointers? btw I'm an exchange administrator, not a netbackup operator.

If it helps this is from the event log on the exchange box, this event is recorded each time I get the error 'Netbackup has encountered an error and needs to close':
--------------
Reporting queued error: faulting application tar32.exe, version 4.5.0.2790, faulting module tar32.exe, version 4.5.0.2790, fault address 0x00029ebc.

For more information, see Help and Support Center at

http://go.microsoft.com/fwlink/events.asp.