Unfortunately, you didn't tell us the operating system you're using.. Still, since most "media center edition" statements refer to Windows XP, I'll proceed as if that's the case.
Whenever setting up a new computer, one should create at least TWO separate accounts which have admin rights. If you haven't done such, you can always check to see if there is a "hidden" administrator account like this:
Restart the computer into Safe Mode and hopefully, you have the option to log in as the hidden administrator.. If the traditional login window loads, then you'll need to type in "administrator" into the "username" line, then leave the "password" line empty and press the "Enter" key. (If you've got the Welcome Screen enabled, simply click on the "adminstrator" logon icon, then leave the password line empty and press the "Enter" key.) As long as you've not created a password for such, then the computer will boot to the hidden adminstrator and you can then change your normal user account's password from the Control Panel-User Accounts section.
If you don't find the hidden administrator login on you computer, then you'll need to use a program such as the one below to get it done.
NT Password
http://www.pogostick.net/~pnh/ntpasswd/
Hope this helps.
Grif
i have windows media center edition. ive literally tried everyway possible to gain access to my admin account. i have forgot my password to it. and now i only can access the guest account. i cannot download anything and retrieve my files on my admin. acc. can someone help me out with this problem!
Thanks

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