I am using TD 6.0 to launch winrunner scripts on 4 pcs using one as the host. I randomly receive the following error on any of the pcs:

TestDirector cannot execute the current automated test
The data has been modified by another user and needs to be refreshed.
CRun :: SetRunValue
CBaseAPI :: SetValue
CBaseAPI :: CreateUpdateSQL
CBaseAPI :: CreateUpdateSQL -- No rows affected

The error is noted in the Test Run Scheduler status column. Any idea what this error could mean? Thanks.