The Backup app is ArcServe. v11.5 SP4 before we had this issue the SP was number 3.
We had to reconfigure it the arcserve from scartch, and simultaneous jobs was working just fine we could run up to 8 jobs at once now only one and the other jobs get quued up.
The backup server is Win2003, SP2.
The error is the error is "device busy". For us this is critical we have very important database to run. We already miss and running two days behind with the backups
We also need Arcserve guideline and some pdf documentation.
No help from anyone so far, strange!