Okay, if you are using Windows 8/8.1, follow these steps please:
- Go to PC settings >> PC and devices >> Bluetooth.
- Turn on bluetooth both on PC and your phone.
- Phone is discoverable for only a limited amount of time(approx. 2 minutes), when you find your phone select it and tap Pair.
- Compare the passcodes and press Add to add that phone to your PC's bluetooth devices.
- To send a file from phone to PC, open the file tap share >> bluetooth and select the destination PC.
- To send a file to your phone, right click on that file to open context menu >> Send to >> Bluetooth and select the phone where you want to transfer the file.
Now, if the phone is removed from your bluetooth devices list on PC, you will get error messages. Try reconnecting phone to your PC with steps 1 to 4. Thats it!
Hope it helps.