I had the same problem for weeks
by Uro_Ben - 1/24/12 8:35 PM
In Reply to: Unable to connect Samsung Galaxy S2 to PC using USB by bcadej
I was unable to connect to my phone for several weeks. It was driving me crazy, particularly because it worked at some point in the recent past. After spending hours fiddling with drivers, settings, and many many resets I decided to look at the connector itself. Luckily I have a digital microscope and noticed a lot of "fluff" buried deep in the receptacle. I still wish I took a picture. Well after using come compressed air and a little alcohol and a really small brush, with the power off of course, everything now works... Yippee. The worst part was that I was still able to charge the device so the dirt was not obvious.
<div>Well I now cover the
receptacle with a little rubber tape.</div>
I hope this helps. and if it does please pass on the word.