[Start up error message: The application failed to initialize properly]

Hi, I'm totally new but I thought if I could get help anywhere, it would be here!!

So when I turn my computer on, it goes through the first couple of start up pages but before it goes to the page with the users' names, I get a pop-up error code.

On the top blue bar it says, lsass.exe - Application Error
The application failed to initialize properly (oxc0000005). Click OK to terminate the application.

So I click 'ok' and the error message goes away but all that is left is the black screen, nothing else to click on so I can try to fix it.

Where do I go from here?!

(I'm posting from my laptop, but it is so important that I can get back on my desktop as soon as possible!) Thanks in advance for your help!!!!!

 

As Pete says, things don't look good at the outset with a problem like this.

One thing to try, if you have a full install CD, is to run chkdsk /r after booting the CD to a Recovery Console session.

Another possibility is outlined by this MS Support Article.

Although doing it the way that MS article suggests sounds very involved, you can easily accomplish all that it suggests by using a BartPE boot disk. That will allow you to do all the operations via a GUI as opposed to the command line.

If you had System Restore enabled when the problem developed, there is a good chance that you can return the drive to a healthy state and lose no data. That's the whole gist of the MS article.

If you did not have System restore activated, you will still be able to use the above procedures to allow you to extract your critical files to separate media to protect them in case more drastic measures are eventually needed.