nitaish You did not understand my query. In case of Plesk, once it is installed and then if you try to install the free version of Smartermail, it automatically detects the Plesk software and changes the smartermail license to lite version. This is very helpful for small hosters who can easily save around $1,100 on the Smartermail license. In case of HC, I think it is not supported. I would recommend HC to talk to Smartermail about such an implementation which would be beneficial for the small hosters. BTW, does not HC want more and more people migrate from Plesk to HC? ;)