If you install Sophos with Adguard, you need to disable Sophos web filtering (or close Adguard) or you can't browse, pages doesn't load.
issue from Adguard Github (23 Oct 2015):
Test Adguard with Sophos web protection · Issue #388 · AdguardTeam/AdguardForWindows · GitHub
issue from Adguard Github (23 Oct 2015):
Test Adguard with Sophos web protection · Issue #388 · AdguardTeam/AdguardForWindows · GitHub