When it comes to Microsoft and Windows 7 security they did do something very strange. Basically they made it so Windows 7 was to create default names for the Guest accounts and the administrator accounts, on every copy of the Os.
This basically was put in place in order to make life much easier but what they actually did was make life easier for criminals and hackers all over the world. This was not done on purpose yet it was still done.
However Microsoft does in fact make it easier for you to actually be able to rename these accounts, in order to make it harder for a hacker to make use of these security measures in order to protect these particular accounts.
Renaming the Accounts
If you want to rename the accounts then this is what you need to do:
To rename the Administrator and Guest accounts in Windows 7, begin by logging in to your computer with an account that has administrative privileges. Click on Start then All Programs then Administrative Tools>Local Security Policy.
In the left hand pane, click on the Local Policies folder and then on Security Options. The right hand pane will change its content to show all of the local security options available to you.
In the right hand pane, locate an option titled Accounts: Rename Administrator Account.
Right click on Accounts: Rename Administrator Account and choose Properties from the menu. This will bring up the Rename Administrator Account Properties window. Here you can name the administrator account using any name that is legally allowed by Windows 7. When finished, click the OK button.
On the Local Security Policy window, locate the option in the right hand pane titled Accounts: Rename Guest Account. Right click on this option and again choose Properties from the menu. Rename the guest account to anything you want just as you did the Administrator account above. Click the OK button when finished.
Renaming both the Administrator and Guest accounts on a Windows 7 PC adds more security to your computer. Hackers often strike at operating system vulnerabilities.
Knowing that these accounts are available on every installation of Windows 7, these two accounts are often targets for viruses, malware, and attempts to break into a PC. Rename these accounts and add another layer of security to your computer.
I sincerely hope that this works for you and that it solves not only your problems but that you pass it on to your friends and that it also solves their problems. All the best of luck.