unable to receive email, but can send.
- Thread starter Hesaam
- Start date
Everything looks ok, but it looks like something is blocking, when I ran test smtp was being blocked. Check firewall, not modified exim configuration, possible data center blocking and need to contact them?
mxtoolbox.com
postrategy.co Domain Health
5 Problems
More Info
thanks, how can I fix these errors?Everything looks ok, but it looks like something is blocking, when I ran test smtp was being blocked. Check firewall, not modified exim configuration, possible data center blocking and need to contact them?
postrategy.co Domain Health
5 Problems
Richard G
Verified User
Only the 3rd one is a real error. Failed to connect. The rest are in fact just warnings. DMARC records are good but not required.
Seems your port 25 is closed. Be sure that is open for incoming and outgoing traffic.
If your firewall has it open, you have to contact your datacenter.
Yes, the problem was solved by requesting Hetzner to open port 25. Best wishes.
Just to let you know that I have the exact same problem where I'm able to send but not receive email, and also I have noticed my server ports 25 and 993 are blocked with iptable having filtered status for both ports. I even reset the iptables to default (flush) still having the ports status as filtered. So, I don't think it is an issue with iptables. contacted Linode and they blame my ISP 
Richard G
Verified User
I'm not native English, but this sounds as if you say that port 25 and 993 are blocked by iptables, even with iptables flushed. Is that correct or did I misunderstood?
Just use this command for port 25:
iptables -L -n | grep :25it should return:
Code:
ACCEPT tcp -- 0.0.0.0/0 0.0.0.0/0 state NEW tcp dpt:25
ACCEPT tcp -- 0.0.0.0/0 0.0.0.0/0 state NEW tcp dpt:25If they are at accept, then it depends on where you test from externally. My isp also blocks port 25 outgoing totally nowadays.
So to test it's always best to use another server which surely has port 25 outgoing open or one of the port test sites out there on the internet.
If then the ports are closed, it's youjr datacenter having them closed.
And then you can convince them that way that they are wrong if they are saying it's your ISP.
I tested this within the network, and the result is the same as what you have provided. I tested outside the network, using nmap and this is the result (below is my real test server)
root@MAXIWORK:/home/maxi32# nmap -sV -p 25,80,587,993,443 server.domain.com
Starting Nmap 7.80 ( https://nmap.org ) at 2023-03-12 12:36 +08
Nmap scan report for server.domain.com (17*.**4.50.**5)
Host is up (0.011s latency).
*******
EDIT:
The issue has been resolved by rebuilding the server using a different server image. It is likely that the previous server image had some configuration issues.
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