Gradle sync failed: Connection refused

Question

So I just installed Android Studio again after a long time and it asked me to configure the proxy, so I did. I tested the connection and it worked.

Then it asked me

Answer 1

When I got this error I used Charles Proxy app(even thought Charles Proxy was completely closed). To solve it I just disabled SSL Proxying inside Charles Proxy

After that I got

Cause: unable to find valid certification path to requested target
//and
Connection refused

To solve it just close Charles Proxy(with disabled(stopped) SSL Proxying) and restart Android Studio or analyse traffic and exclude unnecessary host(Proxy -> SSL Proxy Settings... -> Exclude block). In my case it was

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