Gents/Ladies, Fairly tech savvy, but this is driving me nuts. Tried to boot my computer last week and got "lsass.exe" error at bootup, have to close window (this is right after windows bar screen) and then reboots. Tired of messing with it, I format C: drive (have 1 drive with 3 partitions) and reinstall windows xp pro. That worked, but now I can't access third partition mostly (E: = 140 gig). When I try most files, I get "Semaphore Timeout" error. If I don't get that, it just takes FOREVER to read anything on it. Did google search for about 2 hours without success. Trying not to loose the music, pictures, data on that drive. BEGAN with me trying to update windows (as I reinstalled). It gave me error b/c it said that I couldn't write to "E" drive (where it had placed the windows updates, apparently). *SIGH* Any thoughts? I've tried to scan the drive and fix it with System Suite's tools, but hangs on Index checking. Thanks!

Assume you did a Google search for 'Semaphore timeout' (no quotes). I'm surprised that wasn't helpful since there are so many entries that speak, at least somewhat, to your problem. What is the exact error regarding lsass? Assume you've run all the virus scans, AdAware, Spybot, etc. with no success.

You may have a virus, download the newest version and run Stinger which is free and it should find your problem....HTH If you need a simple solution, try mine. I try to give advise on things that have happened to my PC. Changes in registry can be FATAL! Glad to have a chance to help you.

I ran my virus program, which is included in System Suite 5 (its a symantic checker), but it hung on Drive E. (Updated as of yesterday). The stem of the whole problem. Also, Google gives me LOTS of "Semaphore timeout" hits, but they involve laptops, video drivers, DVD programs, etc... Nothing directly talks about this issue as far as Hard Drives and read/write errors. APpreciate the responses though. I'll let the virus checker run overnight to see if it will complete. --P

Sorry, didn't have the "lsass.exe" issue handy (was at work). The exact error was "lsass.exe operation failed. The requested operation was unsuccessful" Now, it COULD be "isass.exe," which is a virus from sasser variety as I have found on the net, but looks like lsass.exe. The confusion was such that I formatted the drive and reinstalled rather than spend the hours figuring it out (I needed clean install anyway). Figured all my important stuff was on partition "E." The one I can't get to now. Heh. Of course. Thanks again. --P

Have you tried letting Windows see if it can fix the problem? Enter "CHKDSK" from a command prompt window and see what it does. You can use "CHDSK /?" to see all of the options available. You might also check in the Disk Management console to see if the drive is showing up at all healthy (right-click My Computer and select "Manage"). Maybe also poke through your Event Viewer log files to see if any errors are being logged related to your problem (so you can check for more info)...

after simultaneos installations of xp on 2 very different computers, I too received the same errorr: "lsass.exe operation failed. The requested operation was unsuccessful" when I reduced the lenghth of the computer name given during installation of xp this problem disapeard for me. good luck to you