I upgraded from 7.6.1 to 7.6.3.4.Build.879 on May 30. Starting this weekend, an 
unusually high number of backups failed, many with an inactivity error message 
in the savegroup report.

This is a 64-bit Red Hat Linux 5.1 box with 64-bit NetWorker. All backups write 
to any of 11 DD Boost devices. No storage nodes are in use. Some of the 
savegroups are set up to clone to LTO-5 tape after their backups finish.

In the daemon.raw file and in nsrwatch, I am seeing errors such as the following

 Mon 02:36:34 PM media emergency: Cannot write to 
/nw11/73/97/d49401a3-00000006-7fd606b0-4fd606b0-00821000-60d99518 - No such 
file or directory
 Mon 02:36:34 PM media info: save set F:\ for client 
remotefile.dental.temple.edu was aborted and removed from volume DDBoost11.001
 Mon 02:36:34 PM media emergency: Cannot write to 
/nw11/43/26/f63a037c-00000006-77d606d1-4fd606d1-008a1000-60d99518 - No such 
file or directory
 Mon 02:36:34 PM media info: save set D:\ for client 
remotefile.dental.temple.edu was aborted and removed from volume DDBoost11.001

I opened a case with EMC open on this, this morning. I restarted NetWorker and 
restarted some of the failed groups. Some of the failed groups are still in 
progress; others have completed successfully. 

The EMC person who first began working with me on this case switched it over to 
someone else, who has not yet picked up the case, but before handing over the 
case, he recommend I upgrade to the  latest DD system OS due to a timing issue. 
I am at 5.0 now. I am a little skeptical of that recommendation.

Has anyone else seen this problem? If so, what did  you do about it to fix it?