Joomla!®Plug

Hi all,

I am new to the site, this is my maybe 100 time visiting a joomla forum, i hope i will find the answer of my question, my question is,

I installed joomla
than smf forum
than roundcube
on my localhost with xampp package

no problem on installation at all but how can i set up from the joomla backend roundcube config to test it in my localhost, i also have mercury mail server with in the package of xampp, i tried everything but cannot login it does not work is there any one can help me out wth roundcube config on joomla and mercury mail as mail server.

thanks