Solved 3cx SMTP Server blocked by DNS Blocklists

[vowa-it]

The 3cx Mailserver (168.245.58.221) is blocked by dnsbl-1.uceprotect.net and other Blocklists.
Registration Mails and Notifications cant be sent. Please resolve.

 

[Agathocles Prodromou]

Hi @vowa-it ,

Despite that IP being in that blacklist, did you actually get any error related to it?

Please provide more details as to what is the issue you are experiencing (describe the issue, not what you believe to be the cause).

 

[vowa-it]

Hi @vowa-it ,

Despite that IP being in that blacklist, did you actually get any error related to it?

Please provide more details as to what is the issue you are experiencing (describe the issue, not what you believe to be the cause).

Hi,

we cant get mails from our 3cx Phone System, because our mail server is blocking these, because the IP is on blocklists.
More customers should have this problem.

 

[TheodorosG_3CX]

If your mail server is blocking the 3CX SMTP then you should allow it from your mail server. This is not a 3CX issue and it does not affect any other installations so far.

 

[vowa-it]

Of course I whitelisted the IP. I just wanted to inform you that the 3CX Mail Server is on blocklists and other customers are affected. Some of them can't adjust their whitelist. Ever thought of that?

If you think that it is not a 3cx problem when the 3cx server is on blocklists then you should not be surprised when other customers have these problems. Your job should be to make sure that your own servers are not on blocklists.

 

[Agathocles Prodromou]

We do take action whenever any of our IPs is blocked on any service, however it needs to be said that the blocklist in question is ignored by most mailservers due to their tactic of randomly blocking ips and asking for money to delist them (without any guarantee that they won't block them again for no reason shortly after - or that they won't block the whole subnet). It is not considered a legitimate blocklist.

 

[vowa-it]

Thank you for your Reply. We will look into this.