Thanks very very much Patrick.
So I created my default web site and everything seems fine yet ! )
Thanks very very much for your help

Hello Arnaud,

Should work with the default certificate of your domain.

Hello Patrick,
The problem with de default certificate is that there's alway that message : MOZILLA_PKIX_ERROR_SELF_SIGNED_CERT and people always write to me to ask what they have to do.
Now, I decided to generate a Let's encrypt certificate because of that and because my default certificate is over (end date was march 2020). I regenerated it but for nextcloud, the old one is still used ...
thanks

Arnaud Forster wrote:

Hello Patrick,
The problem with de default certificate is that there's alway that message : MOZILLA_PKIX_ERROR_SELF_SIGNED_CERT and people always write to me to ask what they have to do.
Now, I decided to generate a Let's encrypt certificate because of that and because my default certificate is over (end date was march 2020). I regenerated it but for nextcloud, the old one is still used ...
thanks

Hello Arnaud,
Sorry, i was not completely clear to you.
I meant the default webserver certificate with Letsencrypt.

My webserer has the Letsencrypt certificate and Nextcloud is running in the same domain e..g DOMAIN.COM/NEXTCLOUD. Therefore it uses the DOMAIN.COM certificate

Maybe what could help is to use a certicate without WWW. So. DOMAIN.COM instead of WWW.DOMAIN.COM
With WWW give me always issues with Nextcloud or Owncloud

I hope this makes it more clear for you and helps.

A single Let's Encrypt certificate can cover multiple domains. E.g my www.mydomain.co.uk certificate also covers mydomain.co.uk, mydomain.poweredbyclear.com, lanserver.mydomain.co.uk, mailserver.mydomain.co.uk and server.mydomain.co.uk. You just specify the additional domains in the Other Domains box when requesting the certificate. The app documentation also covers how to add additional domains to your current certificate.

Hello Nick,
thanks again for your great help, I appreciate it. Yes I saw that you could had some other domains to the certificate. But here, I createa a Let's Encrypt certificate and If I connect to my webconsole https://mywebsite.poweredbyclear.com:81, no worry. This is my Let's Encrypt certificate that is used. But I try to connect to my nextcloud (https://mywebsite.poweredbyclear.com/nextcloud) this is my self-signed certificate that is used and not my Let's encrypt one. So, is possible to change that ?

Arnaud Forster wrote:

Hello Nick,
thanks again for your great help, I appreciate it. Yes I saw that you could had some other domains to the certificate. But here, I createa a Let's Encrypt certificate and If I connect to my webconsole https://mywebsite.poweredbyclear.com:81, no worry. This is my Let's Encrypt certificate that is used. But I try to connect to my nextcloud (https://mywebsite.poweredbyclear.com/nextcloud) this is my self-signed certificate that is used and not my Let's encrypt one. So, is possible to change that ?

Arnaud,

When you certificate is working with https://mywebsite.poweredbyclear.com then it should also work for https://mywebsite.poweredbyclear.com/nextcloud
Did you clear your cache of your browser ?

I've the same setup and this working perfectly.

Thanks Patrick,
Unfortunately, this is not the case here. I dont know if this makes a difference but this is my website on port 81 which use the let's encrypt certificate.
I clear my cache but still having the error..

I saw that when using the port 81, this is my internet name (mywebsite.poweredbyclear.com) that is displayed on my certificate. But when using mywebsite.poweredbyclear.com/nextcloud, this is 'localhost' that is displayed on the self-signet certificate.
Thanks

Arnaud Forster wrote:

Thanks Patrick,
Unfortunately, this is not the case here. I dont know if this makes a difference but this is my website on port 81 which use the let's encrypt certificate.
I clear my cache but still having the error..

What certificate is your default domain using in webserver ? (https://mywebsite.poweredbyclear.com:81/app/web_server)
There you must set the letsencrypt certificate (Digital Certificate)

thanks Patrick. For the while, I've my website.poweredbyclear.com defined in the 'parameter' Server Name but I've no website defined. Should I create one ?

ok, thanks, I'lll but ... to be sure .. because I've several options when creating my defaut website.

Choosing let's encrypt as default certificate is fine but for the other options ... is it important or can deactivate all of them ?

I'd like something as 'closed' as possible

Arnaud Forster wrote:

ok, thanks, I'lll but ... to be sure .. because I've several options when creating my defaut website.

Choosing let's encrypt as default certificate is fine but for the other options ... is it important or can deactivate all of them ?

I'd like something as 'closed' as possible

You can set the most on "Disabled"
I would first try if it is working and then change some settings.