If none of the above steps resolve the issue, you may need to contact Rebellion Support for further assistance. They can help you troubleshoot the issue or provide additional guidance on resolving the error.
: Some users on Steam Discussions found success by launching the game directly via Sniper3Launcher.exe or SniperElite3.exe located in the game's installation files rather than through the Steam "Play" button. Network & NAT Fixes
If you are a friend and get the error, the host (the player who created the session) might have the actual network issue. Ask the host to: