To send and receive email using MercuryMail you need to configure it first - you obviously need to have the MercuryMail server running to do what you want.
There are 2 Windows help files mercury.hlp
in the \xampp\MercuryMail\ folder.
There are forum and support pages:http://community.pmail.com/http://community.pmail.com/forums/default.aspxhttp://www.pmail.com/support.htmhttp://www.pmail.com/
The advanced forum search facility may provide help as this subject has been well and truly covered in the past with some posts having configuration details and troubleshooting tips.