Blackberry445

Windows Task Scheduler claims that my scheduled run of Malwarebytes is occurring but I'm not getting any logs from the software. It runs fine when I initiate it myself and a log is then created. I used the instructions in the software's HELP to create a scheduled task in Windows XP SP3. The same task runs fine on other computers I manage and I'm using the same batch file on the system I'm asking about. Any suggestions?