Hi,
Here are a few documents that could be of help:
* How to correct slow backup performance, slow virus or pre-job scans, and agent initialization problems on fragmented Windows NT, Windows 2000, and Windows 2003 server partitions
http://support.veritas.com/docs/237444
*
http://support.veritas.com/docs/249090
*
http://support.veritas.com/docs/231488
If you are backing up Exchange resources as well, please refer to the following documents:
* Slow throughput while backing up Microsoft Exchange mailboxes
http://support.veritas.com/docs/264851
*
http://support.veritas.com/docs/241858
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