I read similar in a different website ( 
http://www.tek-tips.com/viewthread.cfm?qid=1170654&page=58 ), there are two 
things to look at, retries and parallelism, and perhaps priority of the client; 
the other site's solution sounds like it would solve your problem as you said 
that when it is run alone it succeeds, when running with many other saves it 
could fail as it is probably hitting the parallelism limit which it cannot 
surpass, if you reduce the amount of parallelism your save wants (say from 5 to 
3) see where that puts it, if better, ballancing other saves in same fashon may 
be helpful. Of course if the system goes down, the backup should also, unless 
the machine continues to work after it has no power.

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