I could repeat what everyone else has been saying.
win 7 64
GS 2.1 update 1
On the laptop side:
tried everything, different versions of Kies, uninstalling, cleaning out the registry, cleaning all mention of Samsung, kies off the laptop (except the data I had copied over from the phone.
On the phone side:
tried everything, searched for long file names, ...etc. no use listing it all here. And then, out of sheer frustration, decided I would go for the "Factory data reset (settings, privacy).
It was a bit scary for me, but I went for it. My advice though is to find the steps for doing this, so that you're not worried about what you're doing and what's happening. The upshot is that the phone is back to where it was when I purchased it, fully functioning, but with all user data and user instaled apps erased. But kies (2.0.0.11014_49_2.exe) suddenly recognized the phone, installed the one driver that previously had always failed to install, and connected. Instantantly I was informed that there is new firmware update for the phone, and at this moment I'm in the upgrade process.
I'll add that like so many others, kies connected to my phone when I first bought it. after a week or so, Kies no longer connected expect for mass storage and the other options.
Further, I also tried all the suggestions (prior the reset) on a Win XP 32bit machine, also without success.
That leads me to conclude that the problem was not Kies (I tried about 3 versions), nor the phone (it all worked in the beginning), nor win 64 bit.
The problem, it seems to me, was in some app or combination of apps that i installed.
Once I did the "Factory data reset" it's all working fine.
Once the update completes (or aborts) I'll report on that.
cheers,
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GS Vibrant
Bell