The strangest Photoshop problem I've ever had just came up... I all of a sudden cannot right click, click and drag, use modifier keys (I can push B for brush, but can't say Ctrl-O for open) or long click (I cannot select the secondary tools such as switching between the paint bucket and gradient tools).
I tried deleting my user prefs (had to do it manually because modifier keys aren't working so no Ctrl-Alt-Shift), and that works for literally a few seconds and then the problem reappears. I can't recall doing anything strange to trigger the error; I was using the program just fine and suddenly I couldn't do anything I needed to. I'm having no issues with other software, even other Adobe software. I'm running CS5.5 on Windows 7 Pro. Has anyone encountered this problem before?