I'm running XP on my machine which has worked fine up until about a month ago. No longer does it detect my CD-ROM and CD-RW drives. They arent listed in device manager, they arent listed in My Computer, but the lights still come on and they still open and close just fine. I think I must have uninstalled a program that altered my registry or deleted vital .dll files. Please help! PS, to resolve this issue, I've tried auto-detecting new hardware, I've tried unplugging and re-plugging the drives within the computer itself, and I've tried deleting the UpperFilter and LowerFilter values in regedit under some local_machine/system/currentsettings or something according to a similar problem I read about on a troubleshooting page but nothing seemed to help. Thanks again. -Jebuz

Is your HD connected to primary and cd-rom to secondary? Whats status in "device manager" Is there any dvd/cd-rom drives?

Put your XP cd in the tray and choose install XP and then clean install. Follow along until you get to the screen that asks if you want to REPAIR XP. Choose that option.

Hi Jebuz, If you've followed Grasshopper's advice to no avail, please read this carefully. Although you say that you have checked the Upperfilter and Lowefilter values in the Registry before, why don't you check the procedure again according to the steps below. Maybe the steps you followed were not complete, or were a bit different. You will also find other suggestions below, such as downloading the latest patches for your CD burning software, and so on. What follows is something I have posted for someone else who has the same problem as yours: >>You know, that problem is often caused by Roxio's Easy CD Creator (formerly from Adaptec). Most other burning programs don't normally cause that kind of inconvenience. Nero Burning Rom is an excellent one (http://www.ahead.de/nero). If you have one of these "safer" programs and are still experiencing that problem, some of your system files or the Windows Registry may have become corrupted indeed. Sometimes, downloading and installing the latest patches or updates for your burning software from the right websites helps you solve that kind of problem. At other times, the best solution is to uninstall the program completely and get another one. If installing the latest patches or uninstalling the suspicious burning software does not correct the situation, you might need to edit the Registry manually in order to remove some values which are automatically created during the installation process and left behind after installing a patch or performing an uninstall. Those values prevent Windows from showing and giving you access to CD-R or DVD drives. This is how the problem might be fixed: Go to Start/Run, type regedit and press Enter. In the left panel find the registry keys and subkeys indicated below, click on the [+] signs next to each to expand them downwards and visualize them. When you see the long number/letter combination sub-keys shown below, click ON them, not on their [+] sign. HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\Control\Class\ {4D36E965-E325-11CE-BFC1-08002BE10318} HKEY_LOCAL_MACHINE\SYSTEM\ControlSet002\Control\Class\ {4D36E965-E325-11CE-BFC1-08002BE10318} HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Class\ {4D36E965-E325-11CE-BFC1-08002BE10318} Then you will see different values on the right pane. That's where you should look for and remove the ones called UpperFilter(s) and LowerFilter(s). Just click on those words one at a time, and press Delete to remove them. You'll have to do this for each of the three sets of keys and sub-keys shown above. NOTE: You may only have either the UpperFilter(s) or the LowerFilter(s) values on the right pane. If so, remove the one(s) you have. When you're done, close the Registry Editor window and reboot immediately. Hopefully, you should see your CD drives again. Just be very careful when searching for and removing the Registry values indicated above. Please let us know whether you've been able to solve this issue. Good luck. Juan