Well, that isn't it then ... it could be that your new program for some reason unloads it. Find your acadapp.lsp, acad200xdoc.lsp, acaddoc.lsp and if you have one acad.lsp, also identify if you are having any menus loading besides the standard menu ad expresstools menu (you can use menuload) then identify any mnl files that are loading, each of these may hold a clue as to why the expresstools are being unloaded.