hmmm.
A.)Try rebooting Phone and try again .
B.)Un-install and Reinstall KIES and try again
C.)Close the KIES process in task manager and try again .
D.)Uninstall KIES and try again
E.)Remove the drivers manually and let windows update re-install them automatically and try again
If None of them works
F.)Do a Factory reset of phone and try Again
If that doesnt work
G.)Reinstall windows and let Windows detect drivers automatically .Dont install KIES in this scenario .
If nothing works ,post again we will try to see what can be done .
it's the windows drivers and KIES at fault . Ironically this was my first question at the forums a year ago .