| SYSTEM INFORMATION |
|
| OS type and version |
Almalinux 9 |
| Webmin version |
2.620 |
| Virtualmin version |
2.520 |
| Webserver version |
REQUIRED |
| Related packages |
SUGGESTED |
Hello, in December I purchased a new VPS account and was assigned the IP address x.x.x.x. Now, in January, Hotmail is rejecting emails from that IP address. I have attached the response to the emails being sent. No mass mailings or campaigns are being conducted.
The supplier tells me to do these steps.
-Make sure your email server is not sending spam.
-Close any open relay.
-Check if there are compromised accounts or scripts that send emails.
-Verify that your server’s PTR/reverse DNS matches your hostname.
But the account is new and spam is not being sent, how can I verify those items to release the block.
It may be that the previous user of that IP was a spammer. Some VPS providers seem to be happy to have their IP reputation trashed, especially cheap ones.
Visit mxtoolbox.com and do Blacklist Check and Blocklist Check for your IP to find out how big the problem is.
For several years now, webmail providers have significantly tightened their guidelines for receiving emails—and rightly so.
Many things are checked, which are certainly described in more detail in the linked article by shoulders.
Normally, you should check the following:
- Is your SMTP’s IP blacklisted?
- Are your server’s DNS records OK?
- Is SPF set up correctly?
There are other things that can or must be set up. Usually, webmail providers will send a message saying that the email from your server could not be delivered because… with the corresponding reason.
To get started, tools such as mxtools are helpful for determining whether certain properties of your server or domain are set correctly.
I hope this helps you a little.
Thanks for your reply. I made the necessary configurations with mail-tester and my reputation was 10/10. I also sent the request to lift the block.
When I send emails, I receive this message.
hotmail-com.olc.protection.outlook.com[xx.xx.xx.xx] said: 550 5.7.1
Service unavailable, Client host [xx.xx.xx.xx] blocked using Spamhaus. To
request removal from this list see
https://www.spamhaus.org/query/ip/xx.xx.xx.xx (AS3130). [Name=Protocol
Filter Agent][AGT=PFA][MxId=11BCB31E111A242B]
[DU2PEPF00028D11.eurprd03.prod.outlook.com 2026-01-26T15:25:42.204Z
08DE598F0E04E895] (in reply to MAIL FROM command)
I checked the domain’s DNS settings and this is the result.
Now show this message in test-mailer
SPF: HELO does not publish an SPF Record
According to Outlook’s response, the sending IP (your server) is included in a blacklist at Spamhaus, which is why the remote mail server refuses to accept it.
You should check with Spamhaus (https://check.spamhaus.org/) to see if your IP is listed there and, if so, have it removed.
Since Outlook checks against Spamhaus, I don’t think the problem is with the DNS server you are using. There are already several posts about this here.
I suspect that if you have not entered a correct SPF record for the sending domain, this can quickly lead to you ending up on blacklists because larger mail servers reject you. Or your new server is in an IP range that has been categorically blocked. This happens when neighbouring IP addresses have generated a lot of spam in the past. In this case, entire IP ranges are blocked rather than individual IP addresses. The AS3130 response suggests this is the case.
