Question : Samsung Blackjack phone with Windows Mobile device center ; unrecognized USB device

I am using Vista/Windows Mobile devce center with a Samsung Blackjack phone, connected by USB. All was working well in synching the phone with Outlook until sometime in the last week, when I began to get the dreaded 'unrecognized USB device' message when I connected the phone. I suspect that a recent windows update may have changed something. The phone device shows up under USB devices as unknown and of couse no drivers load and the phone is not functional.

Answer : Samsung Blackjack phone with Windows Mobile device center ; unrecognized USB device

Do a system restore see if it work? If not,

Remove USB entries in Device Manager, and let windows redected and reinstall again. Try see if it works.