Compaq Presario running XP Home for several years suddenly won't boot. I get a Windows alert box saying "Unable to locate object lsass.exe". But when I used NTFS4Dos to check the files on the hard-drive, the lsass file was present in Windows/System32 at the normal size.

Anyone have any idea why Windows SAYS it can't find a file that's clearly there?

We can't boot from an XP cd because like a lot of recent laptops that came pre-loaded with XP, the mfr didn't provide a *boot* CD. They did provide a "Quick Recovery" cd, but that seems to only be able to re-format the hard-drive, which WOULD destroy all personal data since our last backup.

Chkdsk shows that the HD is fine, BTW.

We've been using AVG free EDITION w/ automatic updates, so I'm not overly worried about it being a virus. But stumped as to what the problem *is*. Thanks!It should boot to an XP CD...
Insert the XP CD . power down and re-boot.
You will get a prompt to Press any key to boot from CD...hit a key.
XP will now be entering setup...LET it run.
At the first screen prompt press R to load the Recovery Console.
It will now load the files needed...this takes a little time.
You will next be asked which XP install you are working on hit Enter
There will be a prompt for an admin password if you don't use one hit Enter.
The RC will now load and will take you to a command prompt window.
Type in fixboot and hit Enter...
Remove the XP CD and re-boot.Thanks again, Patio. We're canvassing our friends, and hopefully one of 'em will have an original XP disk. I do want to confirm my understanding that XP computers can boot from any XP disk, as some users have said you have to match version and SP.

Got any ideas re that aspect?Any XP machine will boot to any XP CD...however if you are going to clear the Registration process you will need to install the same version as your liscense is tied to...