BE 9.1.1152 Incremental running fulls

[Operator2]

I have upgraded from BE 9.0.4172 to BE 9.1.1152 and everything seemed to go fine.
01/11/05 an Incremental was run - It took very long and backed up a large amount of data. (5 hrs)
01/12/05 an Incremental was run - Worked O.K. (30 Mins.)
01/13/05 an Incremental was run - Worked O.K. (30 Mins.)
01/14/05 a Full was run - Worked O.K. (5 hrs.)
01/17/05 an Incremental was run - It took very long and backed up a large amount of data. (5 hrs)
01/18/05 an Incremental was run - Worked O.K. (30 Mins.)

Does anybody have any ideas as to why the Incrementals periodically take so long and backup the amount of data like a full?
We do have Virus software running on the servers.

 

[justin2000]

Hopefully this technote may resolve the issue -

http://seer.support.veritas.com/docs/272946.htm