failed backup

hi,

i'm new comer in EMC environtment,

i had a problem with our backup, using Networker.

When i try to backup the SQL (INCREMENT), the job is always error like below, but if i do the backup of SQL (Full) it always success.

savegrp: suppressed 3 lines of verbose output

38006:(pid 4276):A nonrecoverable I/O error occurred on file "Legato#1a308492-e58d-474d-89d4-19e85482c872:" 995(The I/O operation has been aborted because of either a thread exit or an application request.)..

38006:(pid 4276):BACKUP DATABASE is terminating abnormally..

53084:(pid 4276):Processing msdb failed, the item will be skipped.

43709:(pid 4276):Stop time: Wed May 29 17:56:49 2013

:  Backup operation finished with error(s). Refer to the module backup log file for details.

is there got the same problem with me?

thanks before for your help...