If you remove Service Pack 4 (SP4) from a Windows 2000-based computer, your scheduled tasks will NOT run.

The tasks Status is Could not start.

When you inspect the task scheduler log, you see entries similar to:

"Command Prompt.job" (cmd.exe) 6/27/2003 11:10:00 AM ** ERROR **
      The attempt to retrieve account information for the specified task failed; therefore, the task did not run. Either an error occurred, or no account information existed for the task.
      The specific error is:
      0x8004130f: No account information could be found in the Task Scheduler security database for the task indicated.

NOTE: Re-installing SP4 does NOT resolve the problem.

When you install SP4, the credentials database is converted to a SP4-compatible format. When you uninstall SP4, the database is not re-converted to pre-SP4 format, causing housekeeping code, which starts 10 minutes after the Task Scheduler service starts, to remove the tasks credentials.

To workaround this behavior, re-enter each tasks credentials.

NOTE: If you wish to remove and reinstall SP4:

1. Stop the Task Scheduler service.

2. Set the Task Scheduler service Startup type to Disabled.

3. Uninstall SP4.

4. Reinstall SP4.

5. Set the Task Scheduler service Startup type to Automatic.

6. Start the Task Scheduler service.