Win7 Ultimate: Administrator password falure

Hi, I changed the Administrator accounts to a standard users on both computers on Lenovo Y550 laptop and Dell Inspiron 530 desktop. Everything was fine with Lenovo laptop, but on Dell something went not right and the Administrator account somehow would not accept the password that I gave it to. Now I can not get in Admin account, it's hidden and can not make any changes on Dell desktop, the pop-up window for Administrator password would come on every time and ask me for a password, but seems not for the one I gave it to. I checked on forums and tried all I could. Safe Mode did not help either, because it doesn't have full Admin permission, and changing password in SM didn't work also. Any change requires Admin's permission that I don't have anymore. Does anyone know how to fix this problem? By the way there was no problem on Lenovo laptop to change my account from standard user back to Admin. By on Dell...

DancingWind said:

Hi, I changed the Administrator accounts to a standard users on both computers on Lenovo Y550 laptop and Dell Inspiron 530 desktop. Everything was fine with Lenovo laptop, but on Dell something went not right and the Administrator account somehow would not accept the password that I gave it to. Now I can not get in Admin account, it's hidden and can not make any changes on Dell desktop, the pop-up window for Administrator password would come on every time and ask me for a password, but seems not for the one I gave it to. I checked on forums and tried all I could. Safe Mode did not help either, because it doesn't have full Admin permission, and changing password in SM didn't work also. Any change requires Admin's permission that I don't have anymore. Does anyone know how to fix this problem? By the way there was no problem on Lenovo laptop to change my account from standard user back to Admin. By on Dell...

have you tried a blank password??

Blank password? If it just to click ok without a pass? yes I did, nothing happened.

I have a similar problem with Windows 7 Ultimate. Here is a description of what occurred:

Someone disabled an existing account on my friend's desktop and enabled the Administrator account. Avira AntiVir created a popup message requesting the disabling of the administrator account. I told her to use: "net user administrator /active:no" to disable the account, but I forgot to tell her to create another account first. Now she is locked out unable to access the desktop and her folders.

If I were using Vista, this might work. The question is, will it work for Windows 7 Ultimate? Read below:

If you have removed the last Administrator account on the computer, you should be able to boot into Safe Mode to access the Built-in Administrator account. Here's how.
Restart the computer.
As soon as the system starts to reboot, press and hold the F8 Key until you a black screen menu appear.
Select the Safe Mode option and press the ENTER Key.
When the login screen appears, you should see the Administrator account there.
This account does not have a password associated with it, by default.
Select this account and press ENTER.
When Vista starts in Safe Mode, go to Control Panel/User Accounts and change your account back to an Administrator account. Reboot normally.

Never mind. I tried the resolution for Windows Vista and it worked for Windows 7. Thanks for weighing in, seag33k. Here's another post from a Microsoft forum for reference.

In Windows 7 my administrator account has somehow got set to 'guest' so I have lost all administrator access rights on my Dell laptop