1. Make sure Android PC Sync is configured and running in your PC’s system tray.
2. Make sure USB debugging is not enabled on your phone.
a. Go to Settings > Applications > Development.
b. Make sure “USB Debugging” is NOT checked.
3. Make sure you can manually mount your phone to your PC.
a. Connect your phone to your PC.
b. On your phone, select the notification bar.
c. Select "USB Connected", then "Mount."
d. Your phone's SD card should mount to the PC.
e. Check to see if you can browse the files on your phone.
4. Disable any anti-virus software running on your PC.