Wildcards in selection list - Backupexec 2010 R3

Hi

We are doing NDMP backups from a NetApp SAN, and we have a large user folder with 1500 folders in it.

When this backup job starts, it hangs at 1,024 bytes for sometimes up to 12 hours whilst it enumerates the folder structure.

We wish to split this job into smaller batches by backing up folders A-C under one job, D-F under another etc.

If I manually modify the selection list eg: /user/a*.* /subdir the backup fails.

Below is the Selection list details:

//san-name:10000/vol/vol-name/users/a* /subdir/

Could anyone help me get the syntax correct or even advise if what I am trying to do is possible?

I have tried multiple syntaxes, all of which result in a e0001309 - The NDMP server returned a backup error.

Thanks in advance.