Hi,
I am getting this error with my website. Firefox is the ONLY browser which does not recognize my SSL certificate (Let's Encrypt) where this problem is occurring. All other browser (Chrome, Internet Explorer, Opera, Maxthon) handle the certificate great.
Here is the error I am getting: SEC_ERROR_UNKNOWN_ISSUER.
EDIT:Through Google search engine, I've found that it may be a problem with 'chain' file.
Right here:
https://community.letsencrypt.org/t/cert-not-work-in-firefox/5272/11It's about my domain: xxxxx.com
What can I do about this?