Letsencrypt Rookie errors

Hi,

I purchased and installed the Letsencrypt Plugin and i wanted the try it on one of my own accounts before i rollt it out to my customers.

When i try to create a new certificate in the Webinterface i everytime get following error:

Failed authorization procedure. xxx.com (http-01): urn:ietf:params:acme:error:unknownHost :: The server could not resolve a domain name :: No valid IP addresses found for xx.com at /var/www/imscp/gui/plugins/LetsEncrypt/backend/LetsEncrypt.pm line 832.

The Domain is the same like the i-mscp panel and also ip is the same, do i miss some reverse dns entry or anyting?

UPDATE:

Its somhow connected to the i-mscp system domain. I tested it with a customer domain an it worked fine. Is there a way to use a lets encrypt cert for the i-mscp system as well?

Thanks in andvance.

both domains a resolveable and return the same IP Adress

I found the issue. I have a not official Cert for my domain which is used in webmail and the i-mscp gui, therefore i cannot run Lets Encrypt. Thanks for the help!