Hi,
The following is our quiz for testing certificate 1.0.2 addon plugin.
Quiz with Certificate
We did not encounter any problem.
https://drive.google.com/open?id=1GdTQV2oyzcDiSqhDtfQGfg-fONExNqLA
Here is a sample of the generated certificate. It has a background image.
https://qsm.expresstech.xyz/wp-content/plugins/qsm-certificate/certificates/8-37-10%253A38%253A25%2BAM%2B05%252F16%252F2020-7-100.pdf
Please check for the following.
1) Check that the image size is not huge. It should be a file size in kb and not in megabyte.
2) Upload the image to WordPress media folder and copy and paste the direct link to image file into plugin’s option.
3) Disable any file hotlinking prevention setting in web hosting’s control panel.
4) Remove any file hotlinking prevention code from .htaccess file.
5) The certificate is kept with the plugin’s folder, therefore you cannot have a restriction set on your web hosting control panel or .htaccess script from preventing browser to access this file within your WordPress plugins folder. ( remove any security plugin if you have any )
If the above does not help.
Please set your WP_DEBUG and WP_DEBUG_LOG to true.
Debugging in WordPress
Debugging in WordPress
and check your wp-content/debug.log file for any fatal error.
If you encounter a memory exhaust error, please increase your server memory.
You may zip up your debug.log file and pass it to us, if you require our help in analyzing it.
Regards,
Kriti