[solved] internet applications breaking such as Fortnite, Epic Games, Steam, Microsoft Teams, etc.

[William1254253]

I JUST figured this out after struggling with it, and yeah it's been blocking for weeks/months now.

For me it was blocking Epic Games (logins give error AS-3), downloads in Epic Games (such as Fortnite) and some individual steam games, as well as Microsoft Teams logins. 

For some reason kaspersky antivirus messes with the SSL certs and other network traffic in weird ways multiple apps don't like. And it only started recently, because it used to work. So some update kaspersky didn't isn't playing nice. Anyways the particular setting that fixed it for me was:

Kaspersky Anti virus Settings, then network settings, then under Monitored ports where it says select next to "monitor selected network ports", turn off port 443 HTTPS and/or port 80 HTTP from being monitored. 

No idea what this does to the protection (perhaps someone can answer?), but this fixes the issue with all the apps I tested that weren't working before.

 

[harlan4096]

Disabling those 2 ports monitoring may lead to security risk... just try to update Your KAV to the new Kaspersky Standard version.