Hi All, I have a usercontrol in a class library that consists of nothing more than text boxes and labels. I have been using it on tab pages without a problem for a long time. Today I tried to drop it on a form from the toolbox and received a VS error: Failed to create component xxxx System.Runtime.InteropServices.COMException (0x80004005) Adding this project as a reference would cause a circular dependency etc... I've googled but haven't found anything of any help - any ideas ???