Today I installed the launcher and when I launch it I can’t log in, and I get this message. 
I can not enter
@carlfil Try either changing the Default Browser in Windows Settings &/or clearing your browser cache.
If that doesn't work, then you'll want to try adding an exception/exclusion for the FAF Client to the firewall of your AV software &/or Windows Security.
@mostlostnoob Nothing helped. When I close this error, I am redirected to a site where I need to log in, and then I need to attach my Steam account, but it has already blocked me, and I don’t know what to do next.