- Plesk for Linux
Unable to connect to port 465 from Outlook:
Outlook cannot connect to your outgoing (SMTP) email server
Outlook cannot connect to your email server
Mail server and workstation where Outlook is used are located in different subnets.
It is possible to connect from the server to port 465 (993, 995) using telnet:
# telnet 203.0.113.2 465
Connected to 203.0.113.2.
Escape character is '^]'.
Telnet from the workstation fails:
C:\> telnet 203.0.113.2 465
Connecting To 203.0.113.2...
Could not open connection to the host, on port 465: Connect failed
Firewalls on the server and the workstation allow any connections:
# iptables -nL | grep 465
Route tracing shows the following:
C:\> tracert 203.0.113.2
Tracing route to 203.0.113.2 over a maximum of 30 hops
1 <1 ms <1 ms <1 ms gw.example.com [192.0.0.1]
5 <10 ms <10 ms <10 ms server.example2.com [203.0.113.2]
Traffic to the port is filtered by intermediary hosts.
Contact network administrator regarding the issue.