Error BLZOWCLI00000004

I keep getting crashes with this error in the crash log. Always crashes when I launch Overwatch for the first time (after 10-30 sec) and only the second launch “works”, although it still happens mid game sometimes (totally random, sometimes after 10 minutes, sometimes after 1 hour).
I tried:

  • Reinstalling Overwatch and battlenet at least 3 times,
  • Reseting the saved user options in battlenet and deleting temp and local files in APPDATA
  • Uninstalling drivers with Display Driver Uninstaller at least 3 times, tried 4 different drivers for Nvidia
  • I turned off streaming options in battlenet
  • I turned off browser acceleration

Is there anything else I can try or is it one of those “reinstall windows” thing that only helps?