admin account

how do you take back control of administrator account, when an unknown third party, took control of it and set the password, etc.?

Format the harddrive and reinstall. If you have no idea what the 3th party did you cannot trust the computer anymore.

If you really need in to that account, Google for utilities that will let you put in a boot disc and clear any passwords on the system.

How did the 3rd party obtain the password?

SlackmasterK said:

How did the 3rd party obtain the password?

If the user has logged on and has administrator permissions, you don't need their password to change the password:

run elevated cmd.exe, then type

NET USER [username] *

(where [username] is your username and don't forget the * - it's important)

Sound Advice evildictaitor...perhaps they should also consider hiding their server and securing the built-ins while they are at it!!
In CMD you can use the following commands to secure or delete any accounts not needed, and also hide your server (provided server service is started) or workstation from most prying eyes.

The first command will bring up a list of accounts that the machine has configured to use the net.

C:\Users\Administrator>net users

User accounts for \\yourserverorworkstationnamewillappearhere

-------------------------------------------------------------------------------
Administrator            Guest                    IUSR_**********
The command completed successfully.

The second command here shows how to delete unwanted accounts. (Built-in accounts cannot be deleted, they should be password protected and disabled if not being used)

C:\Users\Administrator>net user "nameofaccountyouwantdeleted" /delete
The command completed successfully.

The next command shows you how to hide your server.

C:\Users\Administrator>net config server /hidden:yes
The command completed successfully.

Now we will go one step further and leave a server comment.

C:\Users\Administrator>net config server /srvcomment:"If a key doesn't exist...write it!! - David Andrews"
The command completed successfully.