Renderer seemed to suddenly stop working

[Jay Trees]

As the title mentions, rendering MJML doesn't seem to work anymore and I get this error. It stopped working on my live site too, so I can't help but wonder if recent core and plugin updates may be related to this.

[17-Dec-2020 11:30:53 UTC] PHP Fatal error:  Uncaught GuzzleHttp\Exception\RequestException: cURL error 60: SSL certificate problem: unable to get local issuer certificate (see https://curl.haxx.se/libcurl/c/libcurl-errors.html) in /path/to/wp-plugin/vendor/guzzlehttp/guzzle/src/Handler/CurlFactory.php:201
Stack trace:
#0 /path/to/wp-plugin/vendor/guzzlehttp/guzzle/src/Handler/CurlFactory.php(155): GuzzleHttp\Handler\CurlFactory::createRejection(Object(GuzzleHttp\Handler\EasyHandle), Array)
#1 /path/to/wp-plugin/vendor/guzzlehttp/guzzle/src/Handler/CurlFactory.php(105): GuzzleHttp\Handler\CurlFactory::finishError(Object(GuzzleHttp\Handler\CurlHandler), Object(GuzzleHttp\Handler\EasyHandle), Object(GuzzleHttp\Handler\CurlFactory))
#2 /path/to/wp-plugin[path here was truncated in log] in /path/to/wp-plugin/vendor/guzzlehttp/guzzle/src/Handler/CurlFactory.php on line 201

Any help would be greatly appreciated!

[Silas Meyer]

It seems that your system has an outdated root certificate. Just use the internal rendering engine.

[Quentin]

@silas229 I think so. @grandeljay your certificate on your server may be outdated or bad. You need to check it. Closing since this is not a bug.