Reset your forgotten system password

Face it: compared to Windows 9x's security features, the tinfoil on the top of a tin of Milo is impenetrable. Almost anyone can get past your log-on password just by hitting -- to restart the PC and boot into DOS. Once there, a hacker can delete the PWL files in your Windows directory to disable password protection. For tighter security, you must rely on the CMOS password, which comes into play before Windows loads. CMOS (an acronym standing for Complementary Metal Oxide Semiconductor) is part of the firmware on your motherboard that holds your BIOS code and settings. Once you have enabled the password option in your CMOS setup program, your system will prompt you for the password at boot-up, before it gets to the operating system.

Because there are many different BIOS versions, I can't give you specific instructions. In general, you need to enter your PC's CMOS setup program by hitting the appropriate key at the beginning of your boot process. A screen prompt usually lets you know which key to press - often it's or . When the CMOS setup screen appears, scan the menu choices for User Password or a similar entry. When prompted, type in your password of choice. And be very careful not to mistype. Even if you're an excellent touch-typist, it won't hurt to look at the keyboard this time when you type the password. Warning: if you lose or forget this password, you won't be able to use your PC.

OK, so what if you do forget or mistype your password? Unfortunately, there's no quick workaround, but the first step is to try to find another password that works. Default passwords - also known as backdoors - can be added by the manufacturer of the BIOS, motherboard, or PC. In some cases, when you initially set up your password, the CMOS setup program may ignore what you have typed and instead activate a default password. In that event, call your PC manufacturer - or if need be, the makers of your motherboard and BIOS - and ask whether a default password exists. Also try these words: "AMI", "AWARD SW", "password", and "cmos". These passwords are often case sensitive, so you might try using all-capital and all-lowercase variants.

Failing that, many systems permit you to reset the CMOS contents from the motherboard. Check your computer's or your motherboard's manual for a jumper that can clear the current CMOS password. If the jumper is there, you can just set it and be back in business.

If your system lacks a password reset, you can still hack your way in by using a motherboard jumper to reset the entire contents of the CMOS program. Of course, this wipes out vital system information, including hard disk settings, power settings, and time and date. So write down your hard disk configuration and other key CMOS settings before refreshing the CMOS. Though most CMOS programs auto-detect the hard disk configuration, it won't hurt to have this information handy.

No reset jumper? You can erase the BIOS settings by removing the CMOS battery from the motherboard. The battery is typically a round, metallic unit that rests on the motherboard near the power connector; check your manual to make sure. If the battery is removable, pull it out and keep it out for several hours. It may take a while for the charge to drain out of the CMOS circuitry.

In many motherboards the CMOS battery is soldered down, but don't let that discourage you. If your motherboard has a connector for adding a second battery, you can set a jumper to disable the old battery, wait several hours for the CMOS to drain, and then connect the new battery. If no such connector is present, you'll have to take your PC into the shop to get the CMOS battery replaced. Don't forget to tell the technician to let the CMOS settings clear before replacing the battery.

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Kirk Steers

PC World
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