Email Sending Not Working

Hi, Hoping someone can help me. I manage my own dedicated server (CPanel/WHM). I just added my first website to CloudFlare. I followed all the instructions. Email was not working but after some research in the community I was able to get email receiving working. But it seems I am still having issues sending email. I’m willing to bet its my server is blocking it as I locked it down tight after some malicious PHP mailers were found on the server. For testing, I deactivated ConfigServer Outgoing Spam Monitor and added CloudFlare’s IP addresses to the sending IP address whitelist but still not able to send email… Any ideas?

If that’s true it’s most likely that your IP is listed. Check it with MXToolbox, DNSBL or Ultratools for example.

Thank you! The IP was de-listed from block/black lists about 9 months ago.

I am using Outlook and the mail is not leaving the Outbox.

Ok, that’s a different issue then.

I assume it started right after adding the domain, am I right?
Ensure that the hostname you use to connect with outlook or any other email client is not proxied (:orange:)

Yes, it started immediately after the domain’s nameserver change. I waited 24 hours to be sure it resolved before making any changes.

I followed the tutorial already, but I did go over it step by step once again to be sure I didn’t miss anything.

None of the email proxies are enabled.

Can you share the domain and the hostname your’re using to connect with your e-mail client?

Sure, its, connecting with

That’s strange. I can connect via telnet using Port 25 (smtp) and 143 (imap).

It seems to be a shared mail server so i doubt that this is a result of your recent locks. If you have access to the server log’s I’d recommend to check if you can see the connection attempts from your IP. Or let the host check if they can spot anything.

But Outlook should display an error message if there’s something wrong with the connection. A time out for example.

Here is the Outlook error.
Task ‘[email protected] - Sending’ reported error (0x8004210B) : ‘The operation timed out waiting for a response from the sending (SMTP) server. If you continue to receive this message, contact your server administrator or Internet service provider (ISP).’

I will check the logs to see if I can find anything, at first glance I didn’t see anything related in there.

I checked the track delivery option in cPanel and didn’t see anything there. I tested sending email directly from cPanel’s WebMail and that is working. Seems the issue is isolated to Outlook? I attempted changing the settings in Outlook but no matter what combination of settings I used it still would not work. All other email addresses in my Outlook are sending and receiving without any issues. Checking the log files I don’t see anything.

Did it work before?
It seems the issue is either with your mail client or local network

Try to connect to port 25 via Telnet or use a different Client like Thunderbird or eM Client, just to test the connectivity.
Use a mail client on your mobile and retry via WiFi and 4G
It’s sometimes just a wrong SSL/TLS setting in outlook (SSL/TLS or STARTTLS) if your’re using SMTPS or IMAPS

Rare, but: some ISPs have routers with email abuse detection and pre-configured allowed email servers:

I am running out of ideas. If none of these things work I’d encourage you to re-post your question at Stack Overflow or Server Fault for example. This is going far beyond the scope of this communtiy because Cloudflare’s left out here.

Well oddly enough as I was reading your response I see the little window come up with all my test emails coming through from yesterday. We had just lost power for about 2 hours but my laptop and phone were still receiving emails during that time through cell signal. Only thing that rebooted was the internet modem and router, and that shouldn’t have an affect on it.

I guess its good but I would much prefer to know what happened and be able to provide details on a resolution for everyone… Guess for now I will just enjoy the fact my email works on move on.

Thank you for your help, I really appreciate it!!

Sounds very much like your modem’s public IP was on a blocklist and that the downtime caused the IP to change (which is normal) hence why it’s now working.

Everything else was working, even all other emails (15 email addresses in my Outlook acct). Checked the IP, its the same. I have to whitelist my IP to access my server and all websites to bypass 2FA every time I login so im glad that didn’t change.

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