Error on installing a certificate for domain with Plesk Onyx Plugin

Posted May 19, 2017 3.2k views
UbuntuAPILet's Encrypt

Hi there!

I am accidentily deleted the certificate for a domain in Plesk Onyx on Ubuntu 14.04 LTS Server.
Trying to reinstall a new certificate I receive an error which I have not yet seen in forums:

Fehler: Fehler bei der Installation des SSL-Zertifikats von Let's Encrypt: Could not obtain directory: Invalid response: <HTML><HEAD><TITLE>Error</TITLE></HEAD><BODY>
An error occurred while processing your request.<p>
Reference #97.5df01202.1495194789.2a65bc09
Status: 504.

I have been looking for a solution, but I have not been able to find anything related. Similar errors have been experienced but none has a similar response.

Could anybody help, please?

Thank you very much in advance.

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3 answers


Are you using CloudFlare on the domain by chance? If so, disable CloudFlare on the IP and try to run the script to generate the certificate again. I’ve noticed that in a few cases, since CloudFlare hides the real IP and instead serves with one of their own, the authentication process fails.

It could also mean that you’re using the webroot method and when the script runs, it’s not able to access ./.well-known, which means that directory permissions may be too strict.

What does your Virtual Host block look like?


I have the same problem…
So I don’t use CloudFlare and i take a “root” account to create the certificate, but it doesn’t work.

Let’s Encrypt
Version: 2.1.0-48


Plesk Onyx v17.5.3build1705170317.16 osUbuntu 14.04

  • @marcelaulenbacher

    I’m not 100% sure what paths Plesk uses for their configuration of NGINX, though the default error log is located at:


    If you’re running in to issues, that’d be the file you want to check using something such as:

    tail -20 /var/log/nginx/error.log

    That’ll give you the last 20 lines from the error log (the most recent).

In case of such kind of LE errors you need to check the status of LE services here