Java cannot open localhost:4848. This usually happens because your firewall is blocking access to the server. Try upgrading your firewall or changing the port number for java.

Are you looking for a way to check the availability of a service you’re using on your computer? You could try opening the web browser and entering localhost:4848 into the address bar, but what if you don’t want to install your own web server? If you’re running Oracle’s Java software, there are ways to serve requests using a proxy server. A proxied server allows you to connect to the web server behind a virtual private network, or VPN – which in this case is safely installed on your computer.

YouTube video

localhost:4848 is not responding. Can’t connect to localhost:4848 – Connection refused. Could be due to a proxy or similar problem found in your web server configuration. Try changing your settings and check back regularly for errors.

I get lots of questions from beginners in Java to setting up localhost:4848 in their servers. It is usually followed by, “”why should I do that?”” or “”what is the simplest way?”” I know it might seem obvious to just open a port but before you do that, take a look at the following two topics:

Localhost:4848 is a so-called virtual private server, which redirects all requests to localhost:8080 instead. However, if you try to access localhost:4848 via your browser while you are already at localhost:8080, you’ll get a page like this one: