A couple of things you might try:
Clear your community folder.
Run the sim in admin mode. While in admin mode, you could try re-savings your settings. It may be that your computer is silently forbidding access to the config files.
The only time I know of that the sim draws a frame is the box it uses to show your allotted parking area - that’s a rectangular, light blue/green box. Is this like what your seeing? In which case, you don’t happen to be using an old version of the taxi ribbon add-on, do you? (this would trigger drawing the frame, perhaps wrongly, as soon as you get close.)