Why does this happen?
Basically, when you pair your device, your Bluetooth service generates a unique set of pairing keys. First, your computer stores the Bluetooth device's MAC address and pairing key. Second, your Bluetooth device stores your computer's MAC address and the matching key. This usually works fine, but the MAC address for your Bluetooth port will be the same on both Linux and Windows (it is set on the hardware level). Thus, when you re-pair the device in Windows or Linux and it generates a new key, that key overwrites the previously stored key on the Bluetooth device. Windows overwrites the Linux key and vice versa.
Bluetooth LE Devices: These may pair differently. I haven't investigated myself, but this may help Dual Boot Bluetooth LE (low energy) device pairing
How to fix
Using the instructions below, we'll first pair your Bluetooth devices with Ubuntu/Linux Mint, and then we'll pair Windows. Then we'll go back into our Linux system and copy the Windows-generated pairing key(s) into our Linux system.
- Pair all devices w/ Mint/Ubuntu
- Pair all devices w/ Windows
- Copy your Windows pairing keys in one of two ways:
psexec -s -i regedit.exe from Windows (harder). You need
psexec as normal regedit doesn't have enough permissions to show this values.
- Go to "Device & Printers" in Control Panel and go to your Bluetooth device's properties. Then, in the Bluetooth section, you can find the unique identifier. Copy that (you will need it later).
- Download PsExec from http://technet.microsoft.com/en-us/sysinternals/bb897553.aspx.
- Unzip the zip you downloaded and open a cmd window with elevated privileges. (Click the Start menu, search for
cmd, then right-click the CMD and click "Run as Administrator".)
- cd into the folder where you unzipped your download.
psexec -s -i regedit.exe
- Navigate to find the keys at
If there is no
- You should see a few keys labels with the MAC addresses - write down the MAC address associated with the unique identifier you copied before.
chntpw from your Linux distro (easier). Start in a terminal then:
sudo apt-get install chntpw
Mount your Windows system drive in read-write mode
chntpw -e SYSTEM opens a console
Run these commands in that console:
> cd CurrentControlSet\Services\BTHPORT\Parameters\Keys
> # if there is no CurrentControlSet, then try ControlSet001
> # on Windows 7, "services" above is lowercased.
# shows you your Bluetooth port's MAC address
Node has 1 subkeys and 0 values
> cd aa1122334455 # cd into the folder
# lists the existing devices' MAC addresses
Node has 0 subkeys and 1 values
size type value name [value if type DWORD]
16 REG_BINARY <001f20eb4c9a>
> hex 001f20eb4c9a
=> :00000 XX XX XX XX XX XX XX XX XX XX XX XX XX XX XX XX ...ignore..chars..
# ^ the XXs are the pairing key
Make a note of which Bluetooth device MAC address matches which pairing key. The Mint/Ubuntu one won't need the spaces in-between. Ignore the
- Go back to Linux (if not in Linux) and add our Windows key to our Linux config entries. Just note that the Bluetooth port's MAC address is formatted differently when moving from Windows to Linux - referenced as aa1122334455 in Windows in my example above.
The Linux version will be in all caps and punctuated by ':' after every two characters - for example AA:11:22:33:44:55.
Based on your version of Linux, you can do one of these:
- Before Mint 18/16.04 you could do this:
sudo edit /var/lib/bluetooth/[MAC address of Bluetooth]/linkkeys - [the MAC address of Bluetooth] should be the only folder in that Bluetooth folder.
This file should look something like this:
[Bluetooth MAC] [Pairing key] [digits in pin] 
AA:11:22:33:44:55 XXXXXXXXxxXXxXxXXXXXXxxXXXXXxXxX 5 0
00:1D:D8:3A:33:83 XXXXXXXXxxXXxXxXXXXXXxxXXXXXxXxX 4 0
Change the Linux pairing key to the Windows one, minus the spaces.
- In Mint 18 (and Ubuntu 16.04) you may have to do this:
Switch to root:
su - (In more modern versions of Ubuntu, 'sudo -i')
cd to your Bluetooth config location
/var/lib/bluetooth/[bth port MAC addresses]
Here you'll find folders for each device you've paired with. The folder names being the Bluetooth devices' MAC addresses and contain a single file
info. In these files, you'll see the link key you need to replace with your Windows ones, like so:
- Once updated, restart your Bluetooth service in one of the following ways, and then it works!
- Reboot into Windows - it works!