I'm afraid it's not really an option, but there's another way: Go to your music library, right-click on any mp3 file and select Open With, and find Spotify. The file then opens in Spotify. After this move all the MP3 files should open with Spotify as default.
I hope that helps!
SebastyRock Star 16
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This does address the real issue, as I think many are trying to set it as their media player for their keyboards and such. I don't always have a file ready, and just need to open my media player (spotify).
A good method is to just right click spotify in search or the spotify icon if its on your desktop and pin it to your task or start menu so its easy to access. Sadly theres no way to set as defualt or link to your keyboard for ease of access.
sign in (very important to create the app link in appdata for later) I got an MP3 file, Right clicked and open with. I then hovered over open with another program... Selected "Choose another app" Click More Apps......
Scroll to the bottom... click... "Look for another app on this PC"
then go to the folder containing Spotify (to get this, Right click the spotify Icon and then properties) Example - C://Users/usersname/Appdata/roaming/spotify/spotify.exe Then Clicked open. Nothing happens (don't worry)
Now goto... PCSettings, Apps, default apps, Music Player (should be Groove or Windows) Click it, Select Spotify. Done. Now when I press the Music button on my Keyboard Spotify loads.
If you have a computer for multiple users, you may have to play around as it took ages to get to work on my partners. but on my PC worked first time.
Hope this helps those that just want to click 1 button and load Spotify from their Keyboard etc. feel free to share elsewhere.