Envato Market Plugin Failing to Activate

I have successfully used the Envato Market Plugin for dozens of sites except for one. It is the largest site I manage so was thinking there could be a plugin conflict as I’ve downloaded the plugin about 10 times now thinking there was something wrong with the download. So, I installed on a new site and it worked fine.

The error message says: "Envato Market plugin is not installed correctly. Please delete this plugin and get the correct zip file from https://envato.com/market-plugin/."

Is there a list of known plugins that conflict during install? I am using Salient on this site. Thank in advance!

I am not sure and it should not happen. maybe in your installation files are missing/corrupted. please can you delete the plugin and try to upload the plugin using ftp/cpanel. Also please make sure your website wp version, php and theme all are up-to-date. Thanks

I updated to latest PHP version, deactivated 4 plugins but no luck. Will try to ftp it now and reply with result. .