Often when the friendly URL’s function is enabled on the PrestaShop installation, some clients reported that the PayFast plugin was broken. The fix for this is to make sure that the permissions on the PayFast module and it’s sub-directories and files is CHMOD 0755 or more secure, 0644. If it is 0777, the PrestaShop installation won't see the module and reports an error 404, page not found.
Why isn’t my PrestaShop cart being redirected to PayFast?
or drag and drop files