This is going to sound screwy, but try this for me: Give whatever account you use to run the Scheduled Task EXPLICIT FULL control at the NTFS level for the .BAT file. If the BAT file writes any info, make sure that account has EXPLICIT FULL control of the file/folder being written.
For whatever reason, inheritance on bat files on Server 2008 is a little screwy ONLY when run as a scheduled task.
Justin