If you do not have a BES your computer must be accessible from the internet using either VNC or RDP. To test this you can try using Microsoft Remote Desktop (Start - Run - mstsc.exe) and enter the internet address you use to connect to your computer, is mstsc works over the internet, the Mobile Desktop should work as well.
For more specific details please email our support team,
and they will be glad to assist you and help with your specific configuration issues.