The issuer certificate of a locally looked up certificate could not be found?

Hello everyone,

I have just recently finished setting up and tuning a new nextcloud instance for our use. Everything is working really nicely and the server side tuning of PHP has made the Webui pretty snappy.

The last issue I need to solve before I can get some of my people testing this out as a solution is getting the sync app to work. When I go to configure it I am getting the following error:

Untrusted Certificate

Cannot connect securely to nextcloud.domain.org:

The issuer certificate of a locally looked up certificate could not be found

No certificates could be verified

with Certificate *.domain.org

Organization: My Orginization
Unit:
Country: US

Fingerprint (SHA-256):
Fingerprint (SHA-512):

Effective Date: Mon Sep 10 00:00:00 2018 GMT
Expiration Date: Fri Nov 13 12:00:00 2020 GMT

Issuer: DigiCert SHA2 Secure Server CA

Organization: DigiCert Inc
Unit:
Country: US

As you can see this is a certificate issued by DigiCert. The webui does not have an issue with the cert and the chain cert that is installed for NGINX to use, and I use this cert in quite a few places without issue (some other NGINX and Apache servers) without any issue.

I have searched the forums for this error, and only seem to find references to this happening with a Lets Encrypt cert chain, but I am not sure that applies here. Google searches for that error also don’t yield much of anything that seems to apply to me.

So what do I need to do to fix this? Do I need to get in touch with Digicert, and if so, what do I need to ask then for?

Thanks in advance for the help.

@jrc, how did you manage to solve the problem? I’m facing now the exact same situation, like you did…

I figured out: use of fullchain.pem instead of chain.pem and cert.pem solved the problem!