SSL certificate application fails: HTTP-01 ACME challenge returns 404

[Vishal-Pandiyan]

Operating System

Linux

OS Version

Ubuntu 24.04.4 LTS

System Architecture

x86_64

Docker Version

Docker version 29.6.2, build dfc4efb

Docker Compose Version

No response

Reproducible in Latest Version?

Yes, occurs in the latest stable release

Reproduction Steps

1. Installed
2. Domain Added

Observed Behavior

Description

Applying for a free SSL certificate fails because the HTTP-01 ACME challenge endpoint returns HTTP 404.

The ACME validation server successfully reaches the BillionMail server over port 80, but the challenge request to:

/.well-known/acme-challenge/<TOKEN>

returns:

404 Not Found

Error

Failed to apply for SSL certificate:
invalid authorization:
acme: error: 403 ::
urn:ietf:params:acme:error:unauthorized ::
Invalid response from
http://mail.example.com/.well-known/acme-challenge/<TOKEN>: 404

### Expected Behavior

Certificate Applied successfully

### Supplemental Information

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