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A friend of mine asked me me to fix her daughters netbook. It has a BOOTMNG missing error, so I decided to install windows again. But, windows is not installing, because the BIOS has a password, and nobody knows it. So how to remove this password? I know that this can be done in pc's via removing CMOS battery, and so on. Netbooks have this battery too, right? And no software can be used, because no one can log in on the computer. So is it safe to unscrew to screws on the bottom, and just take it off, wait a few minutes and plug it back in?

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What netbook is it? – Darth Android Aug 2 '12 at 20:38
Asus eee PC 1001PXD – user149961 Aug 2 '12 at 20:41
It is NOT safe to remove the screws on a netbook - they are not meant to be user modified. – Julian Knight Aug 2 '12 at 20:42
Bah, I opened my ibuddie a few months ago and nothing happened. And besides, I was told that either you fix it, or it's garbage. – user149961 Aug 2 '12 at 20:49
Deleted my answer. Definitely looks like Darth and Julian have better options to try. – Tanner Faulkner Aug 2 '12 at 20:52
up vote 3 down vote accepted

From what I have experienced, most machines today have BIOS's with non-volatile memory. In other words, removing the CMOS battery doesn't work anymore. You usually have to call the manufacturer and pay them to send somebody out. I am sure there is a way to accomplish the task their technicians accomplish without having to pay that technician ($80 is what HP usually charges where I work), but sadly, I do not know what it is. The best answer I can give you is that the vendor-recommended and vendor-approved method of removing the password is to pay the vendor to do it. Pretty well expected, yes?

BIG EDIT: This looks worth trying. It has some manufacturer backdoor passwords, and failing success with those, instructions on how to reset the BIOS.

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I won't pay anything. That netbook costs about 200€, and it's a year old, so it would be cheaper to buy a new netbook. – user149961 Aug 2 '12 at 20:50
Thanks. It fixed it. – user149961 Aug 2 '12 at 20:59
@ChristianNikkanen, what worked? The linked page includes two methods to reset the password, including the method that Darth linked to which you said did not work. So you used the short-circuit method? – Synetech Aug 2 '12 at 22:35

Retrieved from here:

Shut down your machine. Remove the battery and disconnect the power adapter. Press and hold the power button for 30 seconds. Reinstall the battery and reconnect the power adapter if desired. This process does the same as pulling the CMOS battery. When you boot up, you should be told to press f2 to go into BIOS or f1 (or something) to load default values. Select F2 and go into your BIOS. Go where the password is set and reset the password to blank or a space. Press F10 to save your BIOS.

This SHOULD work.

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Didn't work. Any other ideas? – user149961 Aug 2 '12 at 20:56
@ChristianNikkanen Googling suggested these as backdoor passwords, try one of them: A.M.I., AAAMMMIII, AMI?SW, AMI_SW, BIOS, CONDO, HEWITT RAND, LKWPETER, MI, and PASSWORD. Long shot in the dark here. – Darth Android Aug 2 '12 at 21:04
Tried all of them. – user149961 Aug 3 '12 at 18:58

As I understand it, the only way to reset these is to do a factory reset (there should be a reset button underneath?) and then restore the OS from the backup partition.

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It really is very rude to downvote without giving a reason. It also does not help others understand what the issue with the answer is. Please don't do it. – Julian Knight Aug 2 '12 at 21:09
For reference to my answer: – Julian Knight Aug 2 '12 at 21:14
You may as well get used to hit-and-run down-voters on SE sites. :-( – Synetech Aug 2 '12 at 22:36
@Synetech: Yes, I am but I like to comment just in case it gives someone a change of heart. ;) I don't mind being downvoted but I'd like to know why. – Julian Knight Aug 3 '12 at 5:47

Depending on your brand and model, this Javascript-based master generator for multiple brands might help. It certainly did for my Dell Inspiron recently.

Open-source code at GitHub and supported vendors are described at Dogbert's Blog: BIOS Password Backdoors in Laptops.

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