Hi,
Is Service Pack 2 from XP installed ?
If so make sure that the firewall settings are correctly set as per the following documents
Backup or restore operations may fail with "0xa000848c - Unable to attach to one of the drives." and "Unable to attach to \\SERVER" after Service Pack 2 has been applied to a Windows XP system.
http://support.veritas.com/docs/269701
Backups fail with "A communications failure occurred on the backup device" when trying to back up remote computers with Backup Exec on a computer running Windows XP Service Pack 2 firewall.
http://support.veritas.com/docs/274793
Verify that the version of beremote.exe on the Windows XP is same as that of the file on the media server.
Try uninstalling the Remote Agent from the XP system and reinstalling again.
Hope this helps.
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