Dell Inspiron 8100 Won't Recognize HD or CD

I just inherited my daughter's Inspiron 8100. Because her system was loaded with spyware and showing all sorts of error messages and was running slower than a snail, I decided to reformat the HD and do a new install of Windows XP. The reformatting went fine but half way through the installation the I started getting messages that the setup couldn't access anymore files. I switched to the install CD from my Dimension 8200 but got the same messages. Then the computer locked up. When I attempted to reboot from the CD, I first got a message that said "NTLDR is missing". I rebooted again and then got a message saying that the system could not locate the HD or optical drive. I went into the BIOS setup and it showed "none" for the HD and "not installed" for the CD. I turned off the computer and created a set of floppy boot disks. I went into Bios set up and made the floppy drive the primary boot drive. I also notice that it now showed both the HD and CD as present. I booted from the floppy just fine. I put the XP CD in and everything just locked up just after the screen asking what I wanted to do (new install). Now I keep getting either the NTLR message or it doesn't recognize the HD or CD ROM. Obviously I can't get past the floppy boot stage. What, if anything did I do wrong and , naturally, how do I fix it? Someone from a Dell forum suggested that I do a BIOS update from a floppy then , using a Win 98 boot disk, reformat the HD and then try installing Windows XP. Somehow not all of that seemed to make sense. I apologize for this being so long, but I felt it necessary to explain all the steps I took that got me into this pickle in order to get an appropriate solution. Thanks for any assistance. Gerry

Update: Okay, I updated the flash BIOS per the suggestion on the Dell forum. I booted up from the XP floppies then onto the CD. Everything was functioning fine until the install stopped because it couldn't find the EULA. When I tried to boot from the CD again, I got "Cannot Find Primary Hard Drive" and "Fixed Optical Drive Not Installed". I booted up from the BIOS floppy I made and both drives were again showing. I tried booting up from the floppies and then back to the CD setup. Just after I got to the screen asking what I wanted to do (install, repair, etc) I got an error message saying Unable to read CD ROM. I then tried my other setup CD and got the cannot find HD and CD ROM message again. I've been through this cycle 4 or five times. I think I've got it licked only to have some error during the beginning phase of the XP install. I'm almost to the point where this laptop may develope wings and try to fly. After dinner, I tried again, starting with the BIOS disk. This time I made all the way to the setup partion screen. When I selected to delete the existion partion to reformat, I got a message saying that it was unable to delete the partion. When I tried to run th Install option I received the following message: An error occured while setup was updating partion information on: 28616 MB Disk 0 at Id 0 on bus 0 on atapi [MBR]. Setup cannot continue. To quit setup press F3." When I atried to reboot I got "NTDLR missing" and the unabe to find hard drive or fixed optical drive". I have a modicom of computer knowledge and can intuit my way around many problems but this has got me stumped. My guess is there is something going on with the BIOS or there is a loose connection where the CD and HD connect to the mother board, assuming that they are in close proximity. All help will greatly be appreciated. With a memory upgrade and new battery, this ole' gal still has some usefull life left. Gerry

Well, whatever Gremlin was causing the problem left as abruptly as it appeared and I've reformatted my HD and am about 1/2 through a clean install of Windows XP. Then comes the anti-virus and anti-spyware followed by all the XP updates. I guess this was one of those twilight zone problems…and hopefully it won't return! Gerry

Everyone, please accept my apologies for such a lenghty set of posts. I really thought I had it solved. Somehow, I managed to boot from the CD and get the HD reformatted again just to make sure any problem data were wiped out. I made it to 18 minutes to go on the XP installation when I started getting error messages about Windows not detecting this that or the other file (too many to write down them all down here). I even tried switching CD's again but no joy. After about five minutes of going around and around everything locks up. I try to reboot and get the message "Primary Hard Drive Not Found" and "Optical Drive Not Found". I'm quitting until I get some answers and before a burst a vessel in my brain! Gerry