"shit run"

If you get this error, it's because your Steam client needs to update to the latest version. Click Steam -> Check for Steam Client Updates and check under Help -> About Steam, the Steam package version should be 1373418487 or higher.

Briefly disable any Anti-Virus or Firewall programs that might interfere with the Steam client update process. (https://steamcommunity.com/discussions/forum/1/864973123454987057/)