I ran into the exact same problem with one of my NetWorker servers after 
upgrading from 7.4.4 to 7.6.1.  I found a thread on the EMC support forums 
about this issue, and the person who started the thread said that after 
working with EMC support they determined it was a bug in version 7.6.1.  
He downgraded to version 7.5.3.2, and the problem went away.  I also 
downgraded the one server that was having this problem and the problem 
stopped.  The person who started the thread on the support forums could 
not provide a BUG ID, so I haven't been able to find out if this issue has 
been resolved in a newer 7.6.1 release.  

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