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When playing with the controls on the start up of my PC I somehow managed to lose my administrator and now can only use my PC as a second user. I have no idea what my administrator pass word is so am unable to sign in and get it back to how it was. I can not even run things like the disc defrag and put new programs on so it will only be a matter of time before I run to a grinding halt. Any help on how to basically install a new administrator or how to get the password would be great. This is a second hand PC and sadly I do not have many of the installation discs that I hope I do not need.