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Issue Emails are not delivered nor received

Be aware that there is no such thing as a new IP address (at least not for Ipv4 addresses). Almost all IPv4 addresses have a 'history' and especially within hosting they are recycled/reused all the time. Every provider has a limited number of IP addresses that they can use, because there is only a finite number of IPv4 addresses available. And they are all distributed. So an IP addresses might be new for you, but has certainly been used before.
 
Oh yes right, it was an abuse of language to say that my IP was new, thanks for pointing out that.

So hopefully it won't take too long for the issue to be fixed.

Thank you guys for your help.
 
So I received a reply from Microsoft saying :
Our investigation has determined that the above IP(s) qualify for mitigation. The block has been lifted, and the IP(s) have been granted increased daily sending limits.

When I check the IP status and details on SNDS, it says:
  • Blocked: no
  • Details: Junked due to user complaints or other evidence of spamming

And the problem remains exactly the same and I can't send emails to Hotmail users.
I've tested my configurations on Mxtoolbox and everything is right. I can receive emails from anyone and send to everyone except Microsoft accounts.

What could be wrong?
 
The message that Microsoft has sent you should also include an explanation that mitigation may take up to n hours. E.g. 12 hours, 24 hours or whatever. The SNDS may take even longer to update. That is a normal process.
 
Hello @Peter Debik and thank you for your reply.
I figured out that it would take time but there's no such indication in the email and I've in fact received it 26 hours ago.
I guess that there's nothing more to do, so we'll see.
 
There can be additional obstacles, and it is also very well possible, that the server is indeed spamming. Have you checked the Linux process list for suspicious processes like "exim" or a "sendmail" process that is continuously under load? Have you checked the processes that your users own, if there are some suspicious processes other than PHP?
 
I've checked for suspicious processes and everything seems to be fine. The server has only been used for 10 days and for now, no user is interacting with it.
I still have the same issue with Hotmail as I send this message.
 
Tested right now with the following results :
DNSBL Blacklist Test Summary249 of 249 tests done.
ResultsNot listed: 239Blacklisted: 3Brownlisted: 0Yellowlisted: 0Whitelisted: 0Neutrallisted: 0Failed: 7
ProcessingAll done
DNSBL Combinedlist Test Summary15 of 15 tests done.
ResultsNot listed: 13Blacklisted: 0Brownlisted: 0Yellowlisted: 0Whitelisted: 0Neutrallisted: 0Failed: 2
ProcessingAll done
DNSBL Whitelist Test Summary33 of 33 tests done.
ResultsNot listed: 32Blacklisted: 0Brownlisted: 0Yellowlisted: 0Whitelisted: 0Neutrallisted: 0Failed: 1
ProcessingAll done
DNSBL Informationallist Test Summary17 of 17 tests done.
ResultsNot listed: 6Blacklisted: 0Brownlisted: 0Yellowlisted: 0Whitelisted: 0Neutrallisted: 11Failed: 0
 
What difference do you think this could make? Besides getting yet another IP that might again be blacklisted, there is no difference. Would it not be a much better solution to check which blacklists the IP is on and to try to get it removed from there (unless it's one of the "pay for removal" lists of course)?
 
Would it not be a much better solution to check which blacklists the IP is on and to try to get it removed from there (unless it's one of the "pay for removal" lists of course)?
But doesnt Microsoft/Outlook use it's own blacklist? Meaning that if you're only listed on their list there isn't much you can do other than to wait it out?
 
But doesnt Microsoft/Outlook use it's own blacklist? Meaning that if you're only listed on their list there isn't much you can do other than to wait it out?
That is true, however if the user had requested a removal and the removal did not lead to success, it can only be for the reason that some other blacklist is interfering. It is thinkable that MS is looking at some others and incorporating their results to their own behavior. However, I am not sure about that.

I can only say that we had many cases where an IP was blacklisted, then after addressing the issue to MS it was unlisted and things worked like a charm. Why it does not work for that one specific user may remain MS' secret.
 
I thought that maybe directly using Ionos servers for mailing would avoid big headaches since we already have a managed server that uses them and everything is perfect. I don't know though if it's because the servers or it's because it's managed.
I'm also worrying about the fact that there will be many other domains that will be hosted on this server and I've never done that before.
 
I recommend using the "outgoing mail limit" that you can configure in Plesk on the Mail Server configuration page to limit the number of allowed outgoing mails per subscription, per domain and per mailbox. Choose a value somewhere between 30 and 80. Spammers normally exceed that limit. In that case no further mails will be sent for an hour and you or the user or both will be informed about it so that you can check the cause.
 
I've checked for suspicious processes and everything seems to be fine. The server has only been used for 10 days and for now, no user is interacting with it.
I still have the same issue with Hotmail as I send this message.
Are unable to send emails to Hotmail/Outlook addresses (ie they bounce back)? Or do your emails end up in the spam/junk folder?

Is it possible for me to use directly Ionos servers instead?
I have no experience with Ionos, so I don't know what services/options they offer. But if they offer an option to use their mail servers, then that might be a solution for you. Having your server blacklisted can be pain in the **a, so this sounds like efficient solution on which you don't have to deal with the blacklist. That is with the assumption that your server hasn't been compromised. (Because if it is, then no matter what you try or do, you'll get blacklisted again one way or the other).

Another option could be to clone your server, obtaining a different IP address that way. There are no guarantees that the IP of your cloned server wont be blacklisted as well (i.e you inherit a contaminated IP) of course.
 
I recommend using the "outgoing mail limit" that you can configure in Plesk on the Mail Server configuration page to limit the number of allowed outgoing mails per subscription, per domain and per mailbox. Choose a value somewhere between 30 and 80. Spammers normally exceed that limit. In that case no further mails will be sent for an hour and you or the user or both will be informed about it so that you can check the cause.
Yes thanks you I have already checked that and I was talking about the proper configuration more than those restrictions. But obviously they need to be set.

Are unable to send emails to Hotmail/Outlook addresses (ie they bounce back)? Or do your emails end up in the spam/junk folder?
They bounce back with an error message that I already posted here.

I'm really considering the option of using Ionos servers but will this impact Plesk configuration (domain emails with Roundcube for ex)?
Also, would this mean that I will only have to change MX records or is it going deeper?
 
I'm really considering the option of using Ionos servers but will this impact Plesk configuration (domain emails with Roundcube for ex)?
Also, would this mean that I will only have to change MX records or is it going deeper?
IDK, could be. It depends on what Ionos offers. Got a link to the mail service you are referring to?
 
Sorry to be that noob but I don't really know what is it. In the DNS records, the MXs point to mx00.ionos.com and mx01.ionos.com if it's about that.
As I mentioned in a previous post, I have no experience with Ionos. So I don't know what services they offer. If you're using MX records that point to an Ionos mail server that indicates, to me at least, that it's probably a full mailbox service. Where email is managed by the Ionos. Using their servers, webmail, ect.

So you would (typically) use that instead of the mail services that run on a Plesk server.
 
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