Additional log info included...

. Executing pdrai with command:
. "C:\\PROGRA~1\\Symantec\\NetBackup PureDisk Agent\\\\bin\\pdrai" --dsid 5 --generate_po --backup --store --snap --dstype 8 --compress --encrypt_on_server --segment_size 262144
.
takeSnapshot(): unable to prepare volume set for snap
Error: 4: resource child process: unable to create snapshot: unknown error
Error: 4: name process: unable to process resource object: unknown error
Error: 4: pdrai main: unable to perform operation: unknown error
*** Error Message ***

Have you been able to resolve this issue? I am having the exact same problem.

What OS is your agent?

Windows 2003 SP2

My experience is that most of these are problems with VSS.  first make sure you have enough free space to do a snapshot (you need at least 300MB free on the volume).

Next, check the event log for VSS errors- if you see any, go poking around the MS knowledgebase.  They put out a lot of patches for VSS that don't make it into the regular service packs.  Make sure you're up-to-date on VSS.

If that all checks out then yeah, try re-installing the client.

There is a chance of PureDisk issues, rather than VSS ones, because it's not vss command that is failing - it's pdrai (whatever it's purpose might be)

Try running pdagent in debug mode.

Change the pdagent.cfg file with higher debug level and enable debugging to file, then run "pdagent --debug" from command line, do not forget to turn the debugging off after troubleshooting.

Abe