Speaking of Fred Vork... Would this be useful in finding out exactly which registry keys are required to run the NT4 shell in Windows 2000? (And eventually one could hope in XP too..) <{POST_SNAPBACK}> Hmm, not really the target function I would say.. But, actually in a far fetched way you can use it to gather some usable keys and knowledge. 1. Install a fresh NT4 install in a virtual environment. 2. Install ART and UnregDll..(grab the one I've attached or use the regtweak found here at the board on various places). 3. Make a "snapshot" of the registry. 4. Rightclick that shell and unregister it. 5. Make another snapshot of that registry. 6. Use compare function. 7. Export BOTH "redo" AND "undo". ..now, if you rightclick the "redo" file and choose edit you can see all the keys that has been deleted/modified/added ..further, if you do the same with the "undo" file you can easily grab specific keys for that particular dll you have unregistered...(also as you will see, labeled with recognizable names ) ...RNG, Cryptographic and user specific keys are of no use..(not entierly true, you can use .DEFAULT and CURRENT on some of them...but that depends on other factors..can't go into that now) Ofcourse the registry of XP and NT4 differs so there will be things to consider, but this should help you localize and get a "feeling" of what that shell are attached to/in. A direct comparison between XP's and NT4's registry using ART I would save as a last step...better to have some knowledge/"feeling" before getting into that. Good Luck! EDIT: I forgot, what do you mean by Fred Vork...? unregDll.zip