ipod touch not recognized in itunes

iOS: Device not recognized in iTunes for Mac OS X

iOS: Device not recognized in iTunes for Windows

Device Not Recognised

http://support.apple.com/kb/TS1538

And Here

iPhone, iPad, or iPod touch not appearing in iTunes

iPod appears in Windows but not in iTunes

The OS X page was helpful -- as far as it went. The bottom of the page referred me to a second item:

http://support.apple.com/kb/TS3540

I had to follow the first 6 steps on this second page. Luckily I didn't need the 14 more steps at the bottom!