You have to unzip the plugin onto your machine, open the folder ‘tags’ > ‘1.0.1’ then drag or cut and paste the woocommerce-frontend-shop-manager.php file to the root of the folder. Then drop the whole folder onto your server if you have FTP access, or just zip it up again and upload it. I was having the same issue, there’s just no .php file in the root of the folder for WordPress to recognize as a plugin. Hope this helps!
