I have a Dell Dimension 9150 XP Home computer which had been infected with a number of malware, including RootKit-Agent.DX, RootKit-Agent.DI and a number of other Trojan Horses. I removed the drive and scanned it on another PC using updated AVG Internet Security. Also checked the Software and User hives o fthe registry on the drive for malware Startup Items, including the WInlogon\Notify section. Everything I could detect was cleaned up. I also ran CHKDSK /f /r on the drive, and some MFT errors were repaired.
Put the drive back in the PC and started it up. No network connection listed. The network connection on the MB, listed in the Device List, shows the yellow exclamation mark. Plus, there are half a dozen miniport drivers and a couple of other devices listed under Network Adapters, all with exclamation marks. It is not possible to delete any of the items - "Failed to uninstall device".
I finally get all of the non-functional Network Adapters items removed, and only the onboard adapter re-appears after reboot, still non-functional. I am unable to get the onboard adapter to work, so I disable it in the BIOS. Thus far, I have attempted to install 3 other NICs, two different PCI NICs and one USB NIC, and none will install correctly. Windows always says the same thing "Cannot Start Device".
I suspected hardware problems so I ran the extended Dell onboard diagnostics, and no errors were detected. Now I suspect maybe a rootkit might be behind this, but I don't really know. Where do I go from here? Unable to connect to Internet. Thanks, Bill