Joomla!®Plug

Hi ok, what i want to know is after installing Joomla i download the file com-roundcubeV1 for joomla and install it from the companents section of joomla, is this the only file to be installed for joomla or i need to install first rounducube than this com file,

by installing only com file in joomla i still get the login page and config section in joomla for roundcube, i tried it wth the imap server it does not give any errors it just reloads the page after submitting the password and user name ans server name no errors i think it is not redricting me to the inbox page do u think this is because of only installing com file.

can you write wat i need to install to run roundcube in joomla

thanks