Run this from a .bat file, from a shortcut in your Start Menu:
IISReset
NET STOP SPTIMERV4
NET START SPTIMERV4

If you see this, after running the script, you probably fixed.  Restart Visual Studio as well to be doubly sure, and F5 to your heart’s content.
image

If that doesn’t fix it, then I guess there’s always rebooting.

Regards from the front,
Joseph