Hi, I was working on a computer that was having problems bootingup up. It says the isapnp.sys file is missing or corrupt. I've followed the advice of putting the windows xp cd in and attempting to repair it by replacing it, but it would not copy the file over. I've attempted to use a program called Eraser that runs in DOS to completely erase the entire harddrive, but even this program has failed to load. When I start the computer it will go to the screen that ask if I want to start in safemode, safemode with networking, safemode with command prompt, or boot normally. If I choose safemode a list of files will flash by and say it is missing isapnp.sys. If I choose normal it will go to the normal windows loading screen with the bar at the bottom, but it will stay there forever. This has to be some horrible virus that has taken over, but how to get ride of it is so hard. Either that or the harddrive is going bad. Any thoughts?

have you tried a floppy with fdisk or the xp cd should allow you to erase/create partitions and you can start anew. Please keep us updated so we know if we helped you or not.

You say you tried to copy the file over ? Did you rename the file in question first and then try??? As far as the wiping the whole drive goes,,, And that not seeming to work either,,, I have had a problem trying to boot to a program that used pc dos,,, and found that by disabling legacy usb support in the bios allowed me to boot into the program,,, There may be some other simple setting in the bios that may work for wiping the drive ,However in My search for a solution to your problem the problem seems to be to simply rename the old file and then copy over from the xp cd,,, Being that isapnp.sys is a device driver file for windows xp I'd first try to rename the file and then copy it over.... All this has to be done from the command prompt , and I'll have to post back with the commands ,,,,, as soon as I can... Unless you state otherwise... or someone else has a better Idea... and or more knowledgeable and posts them first... If it is a virus keeping you from booting Have you tried any anti-virus apps . Like mcaffee stinger??? Well will look into the commands ,, and all to try and help ... Good Luck ! and I'll keep an eve out for some other posts... MSI 845e mb 768 mb ram and a p4 2.4n running xp ,win 2000 advanced server and win 98 SE alot to learn and I know so little !!!!

Microsoft support article This should better show any commands that needed to be used ,,, Have you tried,or want to try, using a BartPE cd rom to browse the disk!!! could then copy it over that way , also by using another computer and copying the file to a floppy ... or onto the BartPE disk itself.. If These suggestions aren't helpful , I apologize in advance ,,, You stated you tried to copy over the file and for some reason or other it didn't work, the only other thing you stated was that you tried to wipe the drive with a utility.... and that didn't seem to work ,, The only options open are either just reinstall or try other settings in the bios to see if it'll boot then... MSI 845e mb 768 mb ram and a p4 2.4n running xp ,win 2000 advanced server and win 98 SE alot to learn and I know so little !!!!

yes, that is the advice i was originally following. when i typed out the rename command it would say file not found. when i would type out the expand command it would say it did not copy any file. i have tried to boot from the windows xp cd, but for some reason it would not allow me to even get to the part where you see the different partitions. it would start to load the kernel.dll and stop there. i have not tried fdisk. if i get a command prompt then i should be able to use fdisk to reformat the entire harddrive, no?

Well The only other option I could think of is to do a couple of things here... One would be to slave the drive into a computer and run a series of programs on it from there namely the anti=virus scans and perhaps chkdsk from there I'd also do the scans for adawareSE and spybot then go into the sys file and try to copy it over from there ,,, I'd also just for Laughs try and run the MEMTEST utility on the other computer to see if the ram in it is ok ,, There was an article that I came across from here,,, Computing.net... that showed someone else having this problem and there was something about the cpu,,,, I believe they just started reseating different cards and cables and then the problem ,,, Just went away,,, Memtest site