iTunes Not Recognizing iPhone

I recently re-installed iTunes on my Windows PC. Ever since that time when I connect my iPhone to sync, I'm asked if it's a "Trusted Computer". I reply yes, enter the code, then, . . . nothing. iTunes never recognizes my iPhone. I wait maybe 5 minutes (just in case), then disconnect and try again later. Always the same thing. What am I missing? I've seen that the "cure" for this is to re-install iTunes, but doing that is what's caused this issue (I was always able to sync just fine up to now). What's the scoop?