Running Sync as a service is available starting from version 2.3. You can set it to run as System, Local Service or current user. It lets you automatically run it in background regardless of whether a user is logged in, which is particularly useful for server use. In other words, it's not necessary to log in to the system to launch the app and start syncing.
If service runs as System or Local Service it's also available to all users on the computer.
Configure Sync to run as a service
Download Sync and launch it.
Check the "Install Resilio Sync as Windows Service" box
Choose the necessary installation option.
If you click "Yes, migrate settings and uninstall existing Sync client", all your Sync shares will be migrated to the new version of the app.
Choosing "No, I want a clean installation" leads to a clean installation of service. You will need to re-share the necessary folders in Sync and connect them to the already existing ones on other peers. So we pick it and click Next.
Enter your Username and Password when asked. Service will be running as current user, Optionally, accounts 'Local System" and "Local Service" can be used, they don't require password.
Sync web UI will be opened in a new tab of your default browser. If you chose to get the settings migrated, the interface should feature all of your "old" shared folders from the previous Sync installation.
If you go to Task Manager -> More details -> Services -> rslsyncsvc -> right click -> Open Services, you will see that Sync service has logged on as your current User (as John Doe in this example). Here you can also Stop, Restart and Start the service.
C:\Users\Your_User\AppData\Roaming\Resilio Sync Service