Please is there a way to allow only known email addresses on my server to send out emails?
Any help is welcome please.
Erm... enable authentication for sending 'to external' on all ip ranges??
Please which options should i set?
Somebody guessed a password? Look in your logs and find spam and see which account authenticated it.
The default hMailserver settings are safe and appropriate for most users.
A poor password is ALWAYS the weakest link.
If the password for a@example.com is easily guessed, then your server will likely end up spewing spam.
Things like 'test@example.com' set with a password of 'test', OR 'admin@example.com' set with a password of 'admin' are unfortunately far too common and are VERY easily abused.
I'm really in trouble now. All messages to my gmail are bouncing back!!!
Remote server (172.217.197.27) issued an error.
Greylisting: !! ENABLED BUT NOT ACTIVATED!!
POP3:   True                              Antivirus:   True !! ANTIVIRUS NOT CONFIGURED !!
There is a total of 448 auto-ban IP ranges.
!! No SMTP Port 25 defined. Direct external SMTP inbound not possible !!
Backup directory C:\MailBK is writable.
Generated by HMSSettingsDiagnostics v1.95, Hmailserver Forum.
You don't allow port 25 communication. Why not?
I ran this tool: LiveTcpUdpWatch.exe and monitored for a while, I saw so much inbound traffic on port 25 from unknown IP addresses. My mail server is typically NOT busy on Sundays, yet i was getting way over 10 inbound requests on port 25 per minute.
It's not imperative to be open IF you are collecting ALL external emails via pop3 (external download).
I stopped my firewall and ran a test, i was able to send and receive from all networks.
I restored the firewall, created an exception just for hMailServer, now all mails are working properly and the spam incidence has stopped.
Mail coming from your mail clients to be on-sent will come to your server via SMTP, perhaps via port 25, but could also be any port that you set. This includes the standard port 465 and 587.
IMAP and POP3 connections to your server, are from mail clients connecting to YOUR server to download mail.
You should NOT add an exception to your firewall for hMailserver, you SHOULD however set exceptions for the ports used by hMailserver.
The spamming is unlikely to have been stopped by removing the firewall rules...in fact I'd expect the opposite to happen. The incoming connections on port 25 are likely to be mail being sent to your server. It may be SPAM, but it may also be legitimate mail. Unless you accept the connection, and test the messages you will never know.
Things are working properly now.
Mails are coming in as expected.
The spam mails have also stopped.