Zoiper3 uses SIP "MESSAGE" messages for the chat session handling under SIP SIMPLE. IM and presence are supported for SIP only. IM and presence are not available in Zoiper Free. To enable Zoiper to use presence you have to open the Settings -> Preferences menu, then go to Accounts -> Select your account -> Advanced and enable publish presence and subscribe presence. http://www.zoiper.com/en/documentation/windows-installation-and-configuration#accounts To be able to see the status of the contacts you will need to edit them and enter the correct presence IDs in their details. Select the contacts tab from the mail Zoiper interface, then select the contact, click More -> Edit . Usually presence id is what you dial to call this person, but it may vary according to the server setup. Presence id most probably is : <user>, _not_ <user@server> form. You will also need to choose the account to be used for presence for this contact.