One of the most important user accounts in any network is the Administrator account. Users that can access this account can pretty much do anything they please.
You definitely don't want the Administrator account falling into the hands of intruders or other unauthorized personnel. Let's look at a couple of ways you can secure this important account.
First, use a strong password. By strong password, we mean really strong. Your password should include numbers, uppercase and lowercase letters, and special signs (e.g., $, #, etc.). Special signs are especially important because some password-cracking programs don't check them and therefore can't crack passwords that contain them.
There are also elements that your password shouldn't contain, including any dates that reference your personal life (such as your birthday), any of your nicknames, historical dates and/or events, your username, or anything similar to your last five passwords.
Second, rename the administrative account. Many admins also create a fake account and name it Administrator. Then you can keep an eye on this account to see if anyone is trying to gain access. (Of course, make sure you don't give any privileges to this fake account.)
To further secure your administrative account, you can also allow logons only from the console (not over the network). If intruders get by the password, they still won't be able to connect remotely to your computers because they won't have physical access to the machine.