I use Draftsight for creating 2d router files from raw dwg files that have been created in Solidworks. I've been pleased with its capabilities and have stopped using my 2005 AutoCad software, which is not 64bit compatible, requiring me to use it through a virtual pc. When I upgraded my Draftsight software to 2015, all my dwg files switch to eDrawing Viewer for their default program. Now Windows 7 won't let me switch back. It won't except that Draftsight is compatible with the files. I can open them open them using the open file command in Draghtsight, but this is a tedious way to open them. Has anyone else had this problem? I'm out of ideas. Does anyone know how to fix this?