problem sending/receiving files by bluetooth

I can't send files from devices to my Macbook Air. I would turn on the bluetooth on my phone and mac, then pair the devices. I would then try to send the file from my phone to my mac, but it would say it failed.

When I unpaired my mac from my phone and try to pair them again, the mac gives me a message that says to try again and put my device closer to the mac. My phone's right next to it, so I don't know why it's saying that.

Then when I tried to send something from my mac to my phone, it worked fine. Which might mean that something's wrong with my phone?

I tried the same thing with the PC Windows 8 I have. Tried to send a file from my mac to the Windows computer and it didn't work. Neither sending, or receiving files worked.

Does someone have an explanation my bluetooth problem?

Thanks in advance if you do.