I have eight seats of 2000i, inherited from a company buyout, with power pak.  Recently one of the Designers came to me and said that his right-click menus had stopped working.  From the drawing he highlights, let’s say, a leader line and RMB.  The menu stopped working and everything from that point on is directed to the COMMAND LINE.   When I do the same, I get a menu where OPTIONS is at the bottom of the list.  Selecting OPITONS gives me a new window for OPTIONS.  Two categories, for this question, Support file search and Working Support search path.  In the first, Support File search path, I have listed ACADM, HELP, Autodesk Shared, Acadm 2000i\, Support, Fonts. Upon APPLY seems to mirror these to the Working Support search path.

I noticed that the other clients had Express in this section but this Designer did not. Somehow it has disappeared! This client was working fine and just stopped!  Ghostbusters!  So, I copied this folder from the working client’s machine to the non-working client’s machine and everything came back.  BUT, the only way that I can keep AutoCAD running, without crashing, is to rename ACADM folder to ACADMx.   I see that their are .dll files in this folder and for some reason with this folder active and in the path AutoCAD doesn't like and crashes.  If I rename ACADM his menu picks come back but I'm not sure what I've disabled in doing so.  This folder does include a lot of .dll files.  

Any thoughts or help in this would be greatly appreciated.