To determine if a port such as 80 or 5432 has been opened on a server, do the following on the machine trying to connect to the server.
Instructions
1. Download the PortQry utility (to download, for information)
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c:\PortQryV2\portqry -n <server-name or ip> -p TCP both -e <port>
If the port is open, it should be listed with status of LISTENING. For example:
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