Reposted from my thread on the R-word Piracy community

1. Open an elevated command prompt and enter the following commands in order to deny write access to the Spotify update folder, which prevents Spotify from updating:
   icacls "%localappdata%\Spotify\Update" /reset /T (if you haven't ever had Spotify installed, an error here is fine)
   del /s /q "%localappdata%\Spotify\Update" (again, an error is fine)
   mkdir "%localappdata%\Spotify\Update"
icacls "%localappdata%\Spotify\Update" /deny "%username%":W

2. Uninstall Spotify, and reinstall an older version. I'm using 1.0.98.78.gb45d2a6b, which I got from FileHorse.

3. Install BlockTheSpot. (Note: if you're using the version of Spotify I mentioned in the last step, install BlockTheSpot v0.12 instead of the latest version. Installation instructions are found on the main BlockTheSpot page.)

4. (Optional) As a safety measure, use SpotMyBackup to export your playlists into a neat JSON file which you can use to import your playlists back into a new account should you get banned.

The only downside to this is that you'll constantly have the "an update is available" notification, but functionally everything works fine. Just ignore the notification.

Pretty simple, but nobody had compiled these three steps into one post yet, so I figured I'd do it just to make people's lives easier when searching this subreddit or Googling around on how to block Spotify ads.