"Why Can't I Connect?" is a network diagnostic tool that makes it easier to resolve TCP/IP connection errors. Use it to diagnose connections to common server types (Microsoft SQL Server, MySQL Server, FTP, SFTP, IMAP, POP3, SMTP, IRC, LDAP, Usenet) and create generic TCP/IP clients and / or servers. Maybe a firewall is blocking the requested port, the port isn't listening, DNS isn't returning the expected address, DHCP hasn't supplied a local IP address, etc.
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