Q: I have a computer that has contracted a bootstrap virus. I want to wipe everything off of the hard drive and install a fresh copy of Windows 7. Can I do this using my Windows 7 upgrade DVD?
A: More and more users are opting to install Windows 7 onto their machines instead of Windows 8. Some have hired me to wipe their hard drives of Windows 8 to install their preferred Windows 7, which requires more finesse.
There are several reasons to wipe the bootstrap of a hard drive, which not only removes any viruses stored in this area but also makes the computer run faster than it did when it was new. This is because all the bloatware has been removed in the wiping process. (Bloatware is the useless software the manufacturer installs onto a new computer. Bloatware can also be difficult to uninstall.)
In computing, a bootstrap loader is the first piece of code that runs when a machine starts. It is responsible for loading the rest of the operating system. If a computer has a bootstrap virus, it will keep infecting itself every time the system is turned on until the bootstrap area is cleaned. In modern computers, the bootstrap is stored in ROM (read-only memory).
If you are looking for a fresh installation, you would be wise to wipe the bootstrap whether or not you have a virus. Among other things, this involves using the bootstrap from external media, not the local hard drive. If you use your Windows 7 upgrade DVD to boot your infected computer, the system will not be able to see the version of Windows installed on the hard drive, so the new Windows installation concludes that you do not qualify for the upgrade. The computer will consider the new Windows 7 software as pirated.
However, the following instructions show a way around this Catch-22. Note that this workaround is not supported by Microsoft, although Microsoft itself uses it (which is how I learned it long ago).
- Install Windows 7 by booting from the upgrade DVD. If Microsoft refuses your product key during installation, simply don’t enter one and move on.
- Once Windows 7 is installed, click the Start button and type regedit.exe
- Navigate to HKEY_LOCAL_MACHINE/Software/Microsoft/Windows/CurrentVersion/Setup/OOBE/
- Double-click MediaBootInstall and change the 1 to a 0 in the dialog box that appears.
- Close RegEdit.
- Open the Start Menu again and type CMD but don’t press Enter. The shortcut to CMD will appear at the top of the Start menu. Right-mouse click on this and choose “Run as administrator." You may need to handle the User Account Control (UAC) warning.
- In the command line window, type slmgr /rearm (There is only one space in this, and it’s after the first r).
- Press Enter and wait for the "Command completed successfully" message to appear.
- Close the command line window and reboot the computer.
- Run the Activate Windows utility by clicking Start, then right-click Computer, then click Properties. The activation link is at the bottom.
- Type in your Windows 7 upgrade product key to activate, or use Microsoft’s automated phone system.
- You’re all done!