but when I Googled 0x80070005: Access is Denied I found a number of hits. However it seems these relate to a Windows Server 2003 based system and not to XP.
In case they help you narrow down the problem, below are two links to articles that mention this error and the resolution methods;
Microsoft's "Access is denied" error message when you run a batch job on a Windows Server 2003-based computer, and
Scheduled tasks; 0x80070005 Access is denied if I click "Apply", but fine if "Okay".
I hope they help, or a Google search for the term above gives you more options.
Mark
I keep getting a 0x80070005: Access is Denied error when trying to schedule SHUTDOWN.EXE. Other scheduled tasks run fine. I even tried creating it under a different admin account I newly created to no avail. I verified in my security settings that every *.exe in my System32 directory was ENABLED. I dont know where else to check on this. I know others must have tried to schedule shutdown but web searches provide no tips on this specific security error.

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