How to resolve the Resilio Sync service "Error 1069: The service did not start due to a logon failure." on Windows

So you restarted your PC and Resilio Sync isn't running. When you try to manually start the service, you get the Could not start the Resilio Sync Service service on Local Computer. Error 1069: The service did not start due to a logon failure. message.

Here's how to fix it:

1. In Services.msc (which I assume you're already in to have seen the error message), right click Resilio Sync Service -> Properties -> Log On
2. (You may be able to skip Steps 2) to 6). I'm just regurgitating what worked for me) Enable the Local System account radio button
3. Click Apply
4. Click OK
5. Click Start the service
6. After the service has started, click Stop the service
7. Repeat Step 1)
8. Click This account:
9. Click Browse...
10. In the Select User windows, click Object Types...
11. Uncheck Built-in security principals
12. Click OK
13. Enter your username in the Enter the object name to select (examples) field
14. Click Check Names
15. Select your username
16. Click OK
17. Enter your user password in the Password: and Confirm password: fields
18. Click Apply
19. Click OK
20. Repeat Step 5)

Resilio Sync should now start normally.