Stunnel stopped working in last day or so

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My domain is:

I ran this command: I am using stunnel on my server to serve POP3S protocol - I am trying to get mail using an iPhone and another use using an iPad - we are both getting certificate validation errors

It produced this output: Invalid cert

My web server is (include version): stunnel not web (4.56 on i686-pc-linux-gnu platform)

The operating system my web server runs on is (include version): linux (centos 5.11)

My hosting provider, if applicable, is: Simply Virtual Servers

I can login to a root shell on my machine (yes or no, or I don't know): yes

I'm using a control panel to manage my site (no, or provide the name and version of the control panel): no

The version of my client is (e.g. output of certbot --version or certbot-auto --version if you're using Certbot): acme v2.9.0

Further info:

This is the top part of the stunnel config - it is using fullchain.pem

cert = /etc/ssl/letsencrypt/
key = /etc/ssl/letsencrypt/

chroot = /var/run/stunnel/
setuid = nobody
setgid = nobody
pid = /

socket = l:TCP_NODELAY=1
socket = r:TCP_NODELAY=1

CAfile = /etc/ssl/letsencrypt/fullchain.pem

Hi @Shardy, welcome to the LE commjnity forum :slight_smile:

Probably NOT.

I'd try changing these two lines:


cert = /etc/ssl/letsencrypt/fullchain.pem
CAfile = 


cert = /etc/ssl/letsencrypt/fullchain.pem
CAfile = /etc/ssl/letsencrypt/fullchain.pem

Thanks so much, the first suggestion works great! And thanks for the welcome - it's a testament to how well LetEncrypt works that I have never had to join this forum previously despite using LetsEncrypt certs for a number of years now :slight_smile:

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