Odd thing. I had no problem connecting my phone after having installed Kies but my wife's (same exact model) wouldn't. I installed the Samsung USB drivers and both connected fine.

Post w/link to drivers: http://androidforums.com/verizon-ga...e-step-step-rooting-flashing.html#post4789579

 

Samsung tech support knows there is a problem with the mtp driver. It works for some and fails for others. Hopefully they will release a working driver in the future. A major flaw for such an important smartphone and hard to believe they not only screwed up but have not fixed this yet.