- TCP 25 is open on your firewall and redirected on NAT (if required) to your Exchange serverYes, its open
- TCP 25 is open on your server (netstat -an)i see the connection to the server on 25, and random outgoing
- You can telnet from inside to your exchange server TCP 25 and get response (Exchange service may be down if can not connect)from inside i have no issue sending telnet email
- You can telnet from outside to your exchange server TCP 25 and get response (review your firewall config, may be blocked by your firewall or your ISP).oh god, my isp was a nightmare, i was waiting to give blood sample....
- You can receive anonymous emails (this discards missconfigured smtp)not 100% sure if i know honestly
- You have got on your public DNS mail host and MX record pointing to your mailserver.hasnt changed for years..... like 10+, but i did check after i found my black book of passwords
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- TCP 25 is open on your firewall and redirected on NAT (if required) to your Exchange server
- TCP 25 is open on your server (netstat -an)
- You can telnet from inside to your exchange server TCP 25 and get response (Exchange service may be down if can not connect)
- You can telnet from outside to your exchange server TCP 25 and get response (review your firewall config, may be blocked by your firewall or your ISP).
- You can receive anonymous emails (this discards missconfigured smtp)
- You have got on your public DNS mail host and MX record pointing to your mailserver.