Outside mirror will not fold - my solution
 

Of the three Boxsters that I have or had only two of the six mirrors would fold with a reasonable amount of pressure applied.
I had to reglue the mirror on one, and while doing that I saw that the hinge mechanism was broken and had been epoxied in place. No problem I just won't try folding that mirror.
On the Boxster S I just bought the driver's side mirror wouldn't move, so I took it off to inspect the hinge and figure out what to do.
I didn't really have to take the mirror apart to fix it in the end. What I ended up doing was using a plastic upholstery tool to pry around the mating point of the two parts of the mirror and spraying a light oil into the crack that opened up. The hinge uses a spring so normally prying on it enough to open up a crack won't hurt anything.

http://986forum.com/forums/uploads02...1664374921.jpg

The next day, voila, it worked.

The disassembly of the mirror was not a total waste of time because I verified that the hinge was OK and I found that the mirror was separating from its pad so I glued it back in place.

I'm going to check the other mirrors on my cars and my friend's for loose mirrors, it could be that at about 20 years is when the original glue fails.