LG VN271 (Cosmos Touch 2)
- No diagnostic mode required.
- Make sure phone is in diag mode. (if applicable)
- Ensure port on phone is clean, brush out if necessary.
- Check for proper cable and snug connection to phone port.
- Unplug computer side of USB cable, wait 3 seconds and plug into different usb port.
- Reinstall drivers for your mobile device. Use Device Manager to ensure you dont have any driver conflicts and the phone is showing up properly.