Script error at time of previous schedule

I receive the following error:

1    Error    9/1/2009 10:00:03 PM    No such script "E7790CCA-B6BB-42D0-945D-80C08AA2B935"
2    Warning!    9/1/2009 10:00:03 PM    Failed to process pair script:E7790CCA-B6BB-42D0-945D-80C08AA2B935

I previously had a backup scheduled for 10 pm, but I changed the schedule on the task to another time.   Every week I get this error even though there is nothing scheduled. 

What do I need to do to resolve?

Thanks.