How to Reset / Remove / Bypass Forgotten BIOS or CMOS Password
BIOS passwords are used to add some extra security to computers.
You can either set a password to prevent access to BIOS settings or to prevent PC from booting. There are many known ways to reset/remove/bypass the password:
- By removing CMOS battery
- By using motherboard jumper
- By using MS DOS command
By using software By using Backdoor BIOS password By Removing CMOS Battery:
Almost all motherboards use a small coin-sized CMOS battery to store all BIOS settings along with the password. To reset the password, unplug the PC, open the cabinet and remove the CMOS battery for approx. 15-30 minutes and then put it back.
It’ll reset all BIOS settings as well as the password and you’ll need to re-enter all settings. If it fails, then try to remove the battery for at least one hour.
By Using Motherboard Jumper:
Almost all motherboards contain a jumper that can clear all CMOS settings along with the BIOS password. The location of this jumper varies depending upon the motherboard brand. You should read your motherboard manual to check its location.
If you don’t have the manual then look for the jumpers near the CMOS battery. Most of the manufacturers label the jumper as CLR, CLEAR, CLEAR CMOS, etc.
When you find the jumper, look carefully. There will be 3 pins and the jumper will be joining the center pin to either left or right pin. What you need to do, is remove the jumper and join the center pin to the opposite pin.
e.g. if the jumper joins the center pin to the left pin, then remove it and join the center pin to the right pin. Now wait for a few seconds and then again remove the jumper and join the center pin to the left pin.
Make sure to turn the PC off before opening the cabinet and resetting the jumper.
By Using MS-DOS Command:
This method works only if you have access to the system when it turned on because this method requires MS-DOS. Open Command Prompt from the Programs menu and provide the following commands one by one:
debug o 70 2E o 71 FF quit
NOTE: The first character in the above commands is the English alphabet “o” and not the number 0.
After providing the above commands, restart your system and it should reset the CMOS Settings along with the BIOS password.
If you are curious to know how it works? then let me explain the above commands:
In this method, we are using the Debug tool of MS-DOS. The “o” character present at first in these commands, outputs the values to IO ports. The number 70 and 71 are port numbers which are used to access CMOS memory.
By providing FF value we are telling CMOS that there is an invalid checksum and it resets the CMOS settings as well as the BIOS password.
By Using Software:
There are a few software which can also reset CMOS settings or BIOS password or both within a few clicks. But as stated above you should have access to a system which is turned on and should have access to MS DOS or MS Windows:
By Using Backdoor BIOS Password:
Some BIOS manufacturers put a backdoor password in BIOS which always works irrespective of what password you have set in BIOS. Its a master password which is used for testing and troubleshooting purposes.
AMI BIOS Passwords:
A.M.I. AAAMMMIII AMI?SW AMI_SW AMI BIOS CONDO HEWITT RAND LKWPETER MI Oder PASSWORD
AWARD BIOS Passwords:
01322222 589589 589721 595595 598598 ALFAROME ALLy aLLy aLLY ALLY aPAf _award award AWARD_SW AWARD?SW AWARD SW AWARD PW AWKWARD awkward BIOSTAR CONCAT CONDO Condo d8on djonet HLT J64 J256 J262 j332 j322 KDD Lkwpeter LKWPETER PINT pint SER SKY_FOX SYXZ syxz shift + syxz TTPTHA ZAAADA ZBAAACA ZJAAADC
PHOENIX BIOS Passwords:
BIOS CMOS phoenix PHOENIX
Misc Common Passwords:
ALFAROME BIOSTAR biostar biosstar CMOS cmos LKWPETER lkwpeter setup SETUP Syxz Wodj
Other Manufacturer BIOS Passwords:
Biostar – Biostar Compaq – Compaq Dell – Dell Enox – xo11nE Epox – central Freetech – Posterie IWill – iwill Jetway – spooml Packard Bell – bell9 QDI – QDI Siemens – SKY_FOX TMC – BIGO Toshiba – Toshiba VOBIS & IBM – merlin
NOTE: All these passwords are case-sensitive and are changed from time to time by manufacturers.