1) Open "Network-Manager" into toolbar and choose "Connection editor"

2) Click to "Add" 

3) Chose "PPTP" 

4) In the "Gateway" field enter the name of the server you want to connect. You can view the entire list of servers  here..

In the "Login" and "Password" fields enter the name and password of your Boxpn account.

And click to "Advanced" button

5) Into "Andvaced Setting" select the following fields : 

•     MSCHAP,
  
•     MSCHAPv2,
  
•     Use MPPE Encryption,
  
•     Allow BSD compression,
  
•     Allow Deflate compression,
  
•     Allow TCP header compression,
  
•     Send PPP echo packets.
  

And click "OK" button

6) Click "OK" to save your new PPTP configuration 

7) Into "Connection editor" select your new PPTP configuration and click this right mouse button, click "Connect"

8) Now you are connect to our server!