Which administrator account are you talking about? The 'real' administrator or your normal "administrator group" account? If it's you normal account do you have another account with administrator privileges?
Rather than wait for answers I'll cover the above three possibilities. If it's something else I'll need more input.
1) If it's the real administrator, this is a fairly easy fix (that I had to do the other day because my OEM set a password for the account).
·Open Control Panel > User Accounts and select the option that allows you to change other accounts;
·Select the Administrator account;
·Turn off password required. Changing this option will not require a password.
2) If it's your own account but you have another account on the system with administrator privileges, the procedures above will work as well here.
3) If it's you own account and no other account has administrator privileges it will be much more complicated.
First, make a try at changing the account you are in to administrator. It's unlikely this will work and would be a major security hole, but it's worth a shot.
If that doesn't work, try booting to a command prompt and activating the real administrator. The procedures at this link attached with this post/answer, will walk you through booting to a command prompt. Once at the command prompt type the following two lines:
Net user administrator /active:yesNet user administratorp@ssw0rD Notes: 1) These two lines can be in any order; 2) "p@ssw0rD" is an example, type any password you ; and 3) The password line may not be needed in your case. I added it because my OEM set a password on my new computer. If they did on yours as well, you would have to boot back to a command prompt to change the password later so may as well do it now. You can always turn it off later.
Once you have the real administrator activated, boot back up and logon to the administrator account. Once there, use the procedure from "1)" above. this third possibility may not work, I've never actually had to try it this way, but it makes logical sense.
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