yes, usually it's just dirt in the security key. some isopropyl alcohol on a paper towel will clean it right up.
sometimes wires or other items in the cabinet can push the handle of the key down a tad and cause the connection to go finicky. make sure everything is out of the way. is some cabinets (IE: the evil EVO) I actually snap the metal button out of the handle to eliminate this issue.
if it's still not picking up the key, check the I/O board, it should have a whole mess of lit up LED's on it. make sure you have 4 on. if you have 3 or less on, it won't work. while you are ther make sure everything is plugged in. better yet, unplug and plug everything back in again (USB, connections, power, etc.)
also check your computer motherboard BIOS battery. you said it's been primarily off. if the battery goes dead sometimes the BIOS loses or corrupts some of the settings. put a new battery in there (CR2032), hook up a keyboard and boot it up and press the DEL key to enter the BIOS settings. do the "reset to failsafe" settings, then the reset to "performance" settings. that should reset everything back to normal.
it's possible the software has become corrupted. you might need to re-install the 2010 software from the CD's. but before you do that, if it still doesn't work, c'mon back and let us know.