AT and you must use it as a member of the Administrator Group. Since most scheduled tasks run in the context of an authorized user you will find that that user needs a password too.
Windows XP help will explain its use.
Here is a link to a list of native commands for XP and clicking on the command will provide instructions and syntax.
http://www.microsoft.com/resources/documentation/windows/xp/all/proddocs/en-us/ntcmds.mspx
What file is for Scheduled Tasks? I want to open it in command line.

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