Can not receive emails but can send.

aidanw

Ive setup mailcow on a VM and its not receiving emails. The only thing I can think of being a problem is that I have it setup through NGINX Reverse proxy mangaer which is the Ip starting with 68, the VM thats hosting mailcow has the IP starting with 94,
Logs below

esackbauer

Why do you want to use the NPM? That only complicates things (it seems you do not yet understand all involved protocols of mailcow like IMAP and SMTP) and makes spam protection more difficult. Mailcow has its own nginx and firewall rules with iptables and netfilter/fail2ban. It does not need a reverse proxy. Reverse proxies is typically only used if mailcow runs on a private/internal network.
Is much easier to just use the 94.xx address, also for spam protection.

aidanw

esackbauer I have it because I also have other things running on the same VM, is it not possible to use NPM with mailcow?

esackbauer But when trying without NPM it also just doesn’t work.

cow-1 | Sun Jan 4 09:03:18 EST 2026 - Using existing domain rsa key /var/lib/acme/acme/key.pem
acme-mailcow-1 | Sun Jan 4 09:03:18 EST 2026 - Using existing Lets Encrypt account key /var/lib/acme/acme/account.pem
acme-mailcow-1 | Sun Jan 4 09:03:18 EST 2026 - Detecting IP addresses…
acme-mailcow-1 | Sun Jan 4 09:03:28 EST 2026 - OK: 94., 0000:0000:0000:0000:0000:0000:0000:0000
acme-mailcow-1 | Sun Jan 4 09:03:29 EST 2026 - No A or AAAA record found for hostname autodiscover.wavehost.org
acme-mailcow-1 | Sun Jan 4 09:03:29 EST 2026 - Found A record for autoconfig.wavehost.org: 94.
acme-mailcow-1 | Sun Jan 4 09:03:29 EST 2026 - Confirmed A record with IP 94., but HTTP validation failed
acme-mailcow-1 | Sun Jan 4 09:03:30 EST 2026 - No A or AAAA record found for hostname mta-sts.wavehost.org
acme-mailcow-1 | Sun Jan 4 09:03:30 EST 2026 - Found A record for mail.wavehost.org: 94.
acme-mailcow-1 | Sun Jan 4 09:03:30 EST 2026 - Confirmed A record with IP 94. but HTTP validation failed
acme-mailcow-1 | Sun Jan 4 09:03:30 EST 2026 - Cannot validate any hostnames, skipping Let’s Encrypt for 1 hour.
acme-mailcow-1 | Sun Jan 4 09:03:30 EST 2026 - Use SKIP_LETS_ENCRYPT=y in mailcow.conf to skip it permanently.

esackbauer

aidanw I also have other things running on the same VM

On which VM? The one of mailcow or the one of NPM?

aidanw

esackbauer mailcow VM Pterodactyl + Paymenter. The main reason why I used NPM is bc ports 80 and 443 were already in use so I thought it would be easier if I just change the ports and use NPM to proxy.

esackbauer

You can do this, but it is against best practices (running other services in the same VM as mailcow) and then things in mailcow get complicated, because mailcow is not only http traffic, its also IMAP and especially the very critical SMTP.
You need separate hostnames for http(s) traffic and IMAP and SMTP traffic. for https you should use something like webmail.yourdomain.com and point it to your NPM, and leave mail.yourdomain.com to your mailcow VM.

you need to edit mailcow.conf and add ADDITIONAL_SERVER_NAMES parameter with the additional webmail.yourdomain.com

aidanw

esackbauer should I change the hostname to webmail.domain.com? or keep it mail.domain.com

esackbauer

Keep it mail.domain.com. And point it to your mailcow vm. Configure webmail.domain.com at your NPM and have it forwarded to your mail.domain.com. Point webmail.domain.com to your NPM VM.

aidanw

esackbauer Yeah now its just not working. might just stick with making its own VM instead of trying to make it all one. I was just trying to consolidate everything into one VM but now it just looks stupid.