With this Database and Port checker you can see if there is a connection to you're database. We do NOT log any of the information you provide in this script.
No Connection:
Check all the details are correct, Database Name, UserName and Password.
If all above is correct and still no connection, it maybe due to firewall or router blocking the connection.
Have you setup Port forwarding in you're router?
Have you allowed the port (inbound Rules (Windows)) through you're firewall?