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中国DOS联盟论坛 » DOS学习入门 & 精彩文章 (教学室) » Clear secrets of MS-DOS View 1,892 Replies 7
Original Poster Posted 2006-05-15 10:02 ·  中国 浙江 温州 电信
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"CMOS password" is what is usually called "boot password", mainly to prevent others from using their own computer, a barrier set up.

There are many ways to crack the "CMOS password", mainly the following types:

I. Change hardware configuration
When the CMOS password is lost, you can first try to change the hardware of the machine and then restart, because if the system finds that the new hardware configuration is different from the original hardware configuration during startup, it may allow you to directly enter the CMOS to reset without a password. The method of changing the hardware configuration is very simple: for example, remove a memory stick or install a CPU of a different model (of course, the motherboard supports it), replace a hard disk, etc.

II. Create your own password cracking file
A. When the system self-test is completed and ready to boot Windows, press the F8 key, select "Safe mode command prompt only" (safe command mode), and then enter COPY CON YK.COM at the DOS prompt. After pressing Enter, enter in the editing environment:
ALT+179, ALT+55, ALT++136, ALT+216, ALT+230, ALT+112, ALT+176, ALT+32, ALT+230, ALT+113, ALT+254, ALT+195, ALT+128, ALT+251, ALT+64, ALT+117, ALT+241, ALT+195, then press F6 to save. Note that when entering the above data, first press the ALT key, then press the number keys on the numeric keypad (pressing the number keys on the top row of the keyboard is not effective), release the ALT key after entering a segment of numbers, then press the ALT key to enter the next segment of numbers... Each time you release the ALT key during input, a random character will appear on the screen, and we don't need to care about it.
After saving and exiting, we directly run the YK.COM file. There should be no prompt information on the screen, and then restart the computer to clear the password in the CMOS. Of course, other settings in the CMOS will also be cleared at the same time, which requires us to reset them.
B. When starting, select the safe command mode, then enter COPY CON YK.COM, and then enter in the editing environment:
ALT+176, ALT+17, ALT+230, p, ALT+176, ALT+20, ALT+230, q, ALT+205, space, then press F6 to save and run this file, and restart the computer to do so.

III. DEBUG method
At the DOS prompt, run DEBUG and then enter:
—o70 18
—o71 18
—q
or
—o70 21
—o71 21
—q
Exit to the DOS prompt and restart the computer to completely clear the CMOS password. Please note that 70 and 71 are two ports of the CMOS, and we can randomly write some wrong data (such as 20, 16, 17, etc.) to them, which will damage all settings in the CMOS. Friends with time might as well try with several more data.

IV. Universal password
If someone sets the security option in COMS as the system, then every time you start the computer, you must enter the correct password. Otherwise, not only can you not enter Windows, but you can't even enter DOS. In this case, we can only rely on the universal password to solve the problem.
AMI's BIOS: AMI ;Sysg
AWARD's BIOS: award ; Syxz; h996; wantgirl;eBBB ; dirrid.
The above universal passwords are almost 100% effective in cracking the CMOS password on 386, 486, and Pentium motherboards, but they are not so effective for PII-level or above motherboards. There are very few universal passwords that can crack new motherboards above PII, and almost no one has heard of them. However, the author found a password - abaubjao, which has successfully cracked the CMOS passwords on more than a dozen motherboards such as the Chenqi 6ATA4 (PIII), Weige MVP4 (K6—2), Benz 160A, 160A+ (PIII), etc. The author doesn't want to keep it to himself and presents it to everyone here.

V. Use tool software
You will find that there are countless software that can crack the CMOS password on the Internet. The author thinks the best software is Biospwds, which is a small software made by a German. When using it, just click the "Get passwords" (obtain password) button gently, and your CMOS password will be fully displayed on the screen. In addition, you can also see the BIOS version, time and other information. Those with conditions can download it at http://www.geocities.com/mbockelkamp (or download it in the "System Tools" of this site).

VI. Discharge
If you are too unlucky and can't crack the CMOS password with the above methods, then there is only this way. Open the motherboard manual, find the jumper for clearing the CMOS settings, and change the short-circuit method as described in the manual to clear the CMOS. What, your motherboard is too old and has no such jumper? Then take off the button battery on the motherboard. Why can't you start the computer after discharging? Put the battery back.
Floor 2 Posted 2006-05-15 10:48 ·  中国 浙江 台州 电信
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The title of the LZ is a bit baffling ---- "Clear MS-DOS Secrets"?

There are many "CMOS password" cracking methods on the Internet!
1. Change hardware configuration
If it's your own computer, since you've opened the computer, it's more convenient to just discharge it directly.
It doesn't seem proper to do this for someone else's computer!
2. Create your own password cracking file & 3. DEBUG method
Since the owner of the computer has set the BIOS, they must have set the highest authority, and won't give you a chance to get to the DOS prompt.

4. Universal password
Now everyone is using new motherboards, and this trick doesn't work either!
5. Use tool software
Again, it's under DOS, generally you won't be that lucky!
6. Discharge
This is the trump card, the most convenient, and the least need for brains! Haha, I have used this one and succeeded!

[ Last edited by afnspy on 2006-5-15 at 10:49 ]
Floor 3 Posted 2006-05-15 15:41 ·  中国 广东 广州 白云区 电信
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Originally posted by majun2008218 at 2006-5-15 10:02:
……The above universal passwords are almost 100% effective in cracking the CMOS password on 386, 486, and Pentium motherboards……


Such an old and outdated post from Mars……

There were posts like this in the forum years ago
----====≡≡≡≡ 我的至爱,永远是MSDOS!≡≡≡≡====----
Floor 4 Posted 2006-05-16 13:01 ·  中国 四川 成都 联通
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Posts from the last century~~
Floor 5 Posted 2006-05-17 18:19 ·  中国 安徽 宿州 泗县 电信
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The title of the original poster is a bit unclear in expression.
Floor 6 Posted 2006-05-26 11:01 ·  中国 重庆 永川区 电信
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Give it a support, the LZ can post more.
Floor 7 Posted 2006-05-28 09:25 ·  中国 安徽 合肥 巢湖市 电信
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I've seen it on other forums long ago, it's something quite old.
Floor 8 Posted 2006-05-28 13:51 ·  中国 广东 广州 电信
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Such an old post still needs to be posted... The title is also made strange...
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