20 days ago - AndrewT - Direct link
That tells me you have a firewall blocking the new eu4.exe in the 1.31.x patches. That can be in Windows or your internet router/modem.

Does it make any difference which starting option you choose when you run EU4 from Steam?  
18 days ago - AndrewT - Direct link
But logging into your Epic account is done outside the game. My suspicion is eu4.exe is being blocked by your firewall , not Epic.

If you just have the standard Windows Defender firewall, eu4.exe (and for good measure paradox launcher.exe) need to be allowed through it, in both the Public and Private domains there. If you use any other one, it will have a similar feature.