One day my laptop got infected by a virus, and I cleaned all those suspected infected files with Avast! Antivirus. I didn't check what kind of files are cleaned, since there are hundreds of it.

Now I realize it is a bad decision. After that, Avast asked me to restart - which I did - and when I boot again, my laptop asked for a password that I never set in my lifetime. It looks like something like this:

The only difference is that the username is my name, not "Administrator"

I tried guessing the password many times but it always fails. I'm afraid that this means two things:

  1. Avast accidentally deleted the Windows system file, so somehow making Windows asking for a password
  2. The virus from earlier sets the password (though this kind of thing didn't occured before Avast cleaned the suspected infected files)

Then I thought, "if I remove the hard disk, I could access it just fine since the password is set in Windows." So I tried to remove the hard disk and turn on the laptop again.

But I was proven wrong!

This is what appears on the screen as soon as the computer is turned on:

Just black and blue "Enter Password" screen

Now I really do not know what to do. I suspect that this is a BIOS password, but I'm not sure at all.

So my question is:

  1. What happened to my laptop, and why?
  2. Is there any solution to bypass or reset the password, so I could access it normally again?

My laptop is a Toshiba Satellite M300.

  • 1
    assuming its a bios password, it might help to mention the make and model of the laptop – Journeyman Geek Mar 20 '13 at 7:04
  • Whoops, sorry! Was in hurry back then. It's a Toshiba Satellite M300. Bought it on 2008-2009. – deathlock Mar 20 '13 at 9:09
  • @deathlock: Can you check that it still occurs when you put the hard drive back in? Are you sure that nobody has been tampering with your laptop and the virus was a result? – James P Mar 20 '13 at 10:10
  • It still occurs. And i'm sure it wasn't done by anyone around here, since no other person in my home is that proficient in computer, and I always lock my room if I go outside. Though I'm not yet sure if it is done by a virus (it might be done by other programs, but my main suspect is the virus). – deathlock Mar 20 '13 at 15:27

This is the BIOS administrator password which you may set in the BIOS setup option. Without giving correct password , you can't even enter into your booting. If you forget your password, give your laptop to the service center. they will remove your password.

  • Thanks. So it seems my suspicion is true that this is a BIOS password. I never set any password on the laptop though. Is there any other way besides contacting the service center? I would like to know a cheaper alternative since Toshiba service centers in my country is infamous for being expensive. – deathlock Mar 23 '13 at 14:12
  • there is no other way.... you cann't reset this password by yourself without knowing the password..... – Venk Mar 23 '13 at 15:33
  • Finally brought it to the service center, and they reset the CMOS battery. Successfully entered booting, Windows screen appeared, then-BAM. It asked for another password. Weird. – deathlock Apr 8 '13 at 7:47

Its the cmos battery, remove the ccmos battery down and login again after that the password will have been removed, you will then set your date and time and after that put in the cmos battery there again...its as good as ice cream

  • 2
    It is not so easy. After removing the battery you have to wait several minutes for the memory to lose the content. Also it could be hard to get to the battery. – pabouk Dec 2 '13 at 7:29

The CMOS battery is dead. Replace the battery to remove the login password.

  • 1
    Dead CMOS battery usually do not cause such problems. It is the contrary -- dead battery causes the password to be removed. – pabouk Dec 2 '13 at 7:51

protected by Community Mar 29 '16 at 5:53

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