"MTP USB Device" driver error (screenshot) when connecting my Galaxy S to my PC in Kies mode -- How can I resolve this problem?
Go to Samsung Kies software, on top left of the window, click the menu > Driver recovery.
Let it reinstall drivers
After driver installation finished, go to your phone, Settings> Application > Development, tick USB debugging mode.
Under USB debugging mode connect your phone to the PC with USB.
It installs correctly!
Disconnect from PC
Untick USB debugging mode
Connect again


and it works!