Technology in terms you understand. Sign up for the Confident Computing newsletter for weekly solutions to make your life easier. Click here and get The Ask Leo! Guide to Staying Safe on the Internet — FREE Edition as my thank you for subscribing!

Why do I get an error that my computer is protected by a password authentication system?


I have a Del Inspiron 600M. When I turn it on, it goes to, “This computer is
protected by [some sort of serial number] password authentication system.
Please type in the primary or administrator password.”

Well, I was always able to get in before, but now it will not accept my
administrator password. Can you tell me why or can I override this so I can use
my laptop again?

In this excerpt from
Answercast #8
, I talk about how a BIOS password is set, how difficult it
will be to recover, and speculate about causes.


Password Authentication System

I have a theory, but the theory is probably not something you’re gonna like. That message (“password authentication system”) preceded by that serial number implies to me that what you’re looking at is a BIOS password. A BIOS password actually kicks in before Windows is even loaded.

So your Windows administrator password would have nothing to do whatsoever with this.

It’s not good news

Now, the reason you won’t like this is because this is something you would have had to have added yourself – or somebody else would have to had to have add – to the BIOS before Windows even boots.

Since you didn’t set it (assuming you would know if you did), then I can only assume that somebody else did. So I would start by seeing if there’s somebody who has had access to your computer who might want to do something like that.

BIOS security

The problem is that a BIOS password is actually fairly secure, depending upon the computer manufacturer. I honestly don’t know of a reliable way to get around it other than to actually provide the password.

You might get in touch with Dell and see if they have an alternative for you. But at this point, I can’t think of a way in; if indeed this is a BIOS password.

Next – Why can’t I make changes to my host file when I am the administrator on this computer?

Do this

Subscribe to Confident Computing! Less frustration and more confidence, solutions, answers, and tips in your inbox every week.

I'll see you there!

5 comments on “Why do I get an error that my computer is protected by a password authentication system?”

  1. I had a Dell XPS420 for some time and it had a jumper on the motherboard. There would be a pair of pins with the letters PWD or something like that printed onto the motherboard somewhere close and there was a connector which if you took it off and started the computer would reset the password, allowing you back in. Since you can do this, there was also a way to lock the box using a padlock so you couldn’t open it to reset the password. I’ve seen those latches on other Dell boxes as well, so I suppose those probably have a jumper like that as well. You should probably check the manual, or look for it yourself if you’re confident and you know what you’re doing.

  2. Mike’s right: most motherboards (at least the ones that I’ve worked with) have a BIOS reset jumper. Normally, you shut down the computer, short the jumper pins (by moving the jumper over one; the third is a “dead pin”), wait a few seconds, move it back, and restart the computer. BIOS settings, normally including the password, will have been reset.

  3. You can Google “Reset bios on Inspiron 600m”
    There are quite a few posts on how to do what you seek. I don’t remember which one, but it does work. I’ve done it in the past. I know it’s alot harder to do on a laptop than a desktop. It involves downloading a iso file & burning a disk you run at start up on the damaged machine.
    Leo’s right, someone put that P.W. on there. I’d find out who & I doubt they’d ever do it to anyone else again! This is why I NEVER LET “FRIENDS” BORROW ELECTRONICS, PERIOD.

    Hope this helps, keep us posted. J.

  4. I had a similar problem that kept occurring with my dell that I always assumed was a virus (even though my anti-virus software never detected anything). My desktop is not password protected, but after I rebooted, it would ask me for a password. It would allow me to boot into safe mode though and I followed the directions on major geeks to eradicate malware (specifically combofix) and once that ran, my computer booted fine..


Leave a reply:

Before commenting please:

  • Read the article.
  • Comment on the article.
  • No personal information.
  • No spam.

Comments violating those rules will be removed. Comments that don't add value will be removed, including off-topic or content-free comments, or comments that look even a little bit like spam. All comments containing links and certain keywords will be moderated before publication.

I want comments to be valuable for everyone, including those who come later and take the time to read.