Cluster Backup With Arcserve

Hi everyone I get some errors when I try to backup cluster servers
Cluster configuration is
2 Compaq servers (standalone servers)
Windows NT 4.0 with SP 5
Oracle 8i server
I install all agents and I didn’t get any errors
Our oracle database backup without any errors
I receive errors only on share folder called CCUV$
It is the Compaq cluster folder that contains the system files for cluster. I try to change the user that i use to backup but still getting the same errors
Thanks a lot for your help