Hi @1khan111,
I would be happy to assist you with this but unfortunately that is a server error and you are going to have to contact your host about this. They will need to examine the server logs and determine what is causing your server to halt during the process.
Also, please see (if you haven’t yet): What are the requirements to run WP-Lister?
Kind regards,
Menchie
WP Lab Support
Plugin Author
WP Lab
(@wp-lab)
It could be some security system from your web host which disallows certain content to be posted/sent to the server. When you save a template, you send HTML and PHP code to the server, which might trigger some ModSecurity rules or a similar system.
If your hoster isn’t able to fix this for you, you can still edit the template files directly via SFTP (as web designers are used to anyway) or move to another hoster.
kind regards,
Matt