Isass.exe - Bad Image

Recently, I downloaded a Microsoft update. After restarting the computer, before getting to the log in screen, a pop up came up.

It said : "The application or DLL C:\WINDOWS\system32\LSASRV.dll is not a valid Windows image. Please check this against your installation diskette."

The background was pitchblack and when I press OK nothig loads but continues to have a blank screen.

This error is repeated in Safe mode.

I cannot run anything through desktop as it does not come up.
My computer is Windows XP and I have had it for a few years. Unfortunately, I was intending to create a back up at the time of the error and was not able to. This means, if possible I wish to retrieve my data.
I have access to one other laptop with internet.


Help would be great.

Hello,
I am the hippiefreakcomputergeek and I will try to help you with this issue.
Please read the following very carefully and follow the steps.
Instead of the last restore point use an older one, two or three back from the last.
Pay close attention to spaces in between commands.

Do you have an original XP disc?
If not,
Here is a link that you can download the recovery console to your desktop.
And here is a link that tells you how to make the disc.
This is used to repair your computer, using the proper utilities.


Step I. Access the recovery console using the OS CD. As suggested already, you need to have your OS CD to repair it.(Or the image you created from the above instructions).

To run the Recovery Console from the Windows XP startup disks or the Windows XP CD-ROM, use the following steps:

Insert the Windows XP startup disk into the floppy disk drive, or insert the Windows XP CD-ROM into the CD-ROM drive, and then restart the computer.
Click to select any options that are required to start the computer from the CD-ROM drive if you are prompted to do so.
When the "Welcome to Setup" screen appears, press R to start the Recovery Console and follow the process until you get to the recovery console command prompt.screen.

STEP II. At the Recovery Console command prompt, type the following lines(in blue) then press enter after.

1. cd \ ( Note: between "cd" and "\" there should be a "blank space" or else the command will not work )
2. cd system~1\_resto~1

If it gives an error "Access Denied" while accessing the folder, follow the method below

cd \
cd windows\system32\config
ren system system.bak
exit

Then restart the computer and follow step I.

3. dir

when you hit it will list all the restore points folders like rp1,rp2……………. we have to see the last restore point to copy the file from a recent backup. If the restore points have more than one page then u have keep on hitting the key to view the last restore point folder.

4. cd rp {the last restore point no. } (Note : Example : cd rp9, if rp9 is the last restore point, where last restore point no.=9 )

5. cd snapshot

Now the command Prompt will look like this c:\system~1\_resto~1\rp9\snapshot> ( Note : restore point 9 assumed for clarity of the content, you have to go to the last restore point folder as described in the previous lines) Now according to the error message we have to copy the appropriate file from the restore point folder.

6. copy _registry_machine_system c:\windows\system32\config\system
7. Type Exit then press enter. your computer should restart and don't forget to cross your fingers