I have a plugin that works most of the time. In the OnConnection method I have: public void OnConnection(object application, ext_ConnectMode connectMode, object addInInst, ref Array custom) { if(connectMode == ext_ConnectMode.ext_cm_UISetup) { ... my logic for adding in my menu item ... } } Under VS2008 my code will not always fire. The connectMode variable is usually 'ext_ConnectMode.ext_cm_Startup' not 'ext_ConnectMode.ext_cm_UISetup', if I change this code to fire on either then I get an error saying: 'A Command with that name already exists' If I loop through the list of commands then sure enough I will find my menu item. But it never shows up in the tools menu where it is suppose to be. I found a couple posts that mentioned that this can happen if the command name changes and the easiest way to determine if it has is to start debugging in the 'QueryStatus' method since it is called before the item is displayed. My 'QueryStatus' method is never called. If I create a macro that runs my plugin command (my plugin adds a menu item which when clicked launches a little window that does stuff) the window pops up as expected and behaves as expected. The plugin appears in the Addin Manager window and works on about half of the machines it is installed on. I am completely stumped. Any help would be appreciated. Thanks -Cam