I'm running Windows 2000 SP4 here. Before you go nuts... How does Windows NT 4.0 Workstation connect to the internet, specifically dialup and dsl connections? I want to run explorer.exe, shell32.dll and comdlg32.dll of NT4 on Windows 2000, which makes W2K run amazingly fast!!! Some W2K apps work or don't (specifically Notepad, Display properties and Internet Connections!!) So, what files do NT4 use to dialup so I can get onto the Net without swapping back to W2K explorer.exe??

you've lost me - you're trying to use NT components in 2k installation? If so - why! Contact M$ ids you need to know which components underpion which functionality in NT or whatever (who else would know - apart from odd investigative developer who's spent months....)