I have the same issue and what I found is windows likes to allocate the ip address for this one randomly. Hold your mouse pointer over the vcdu icon (in your runnings applications in the right corner) after you have launched it on your computer and it will tell you the address to enter into your portable device settings. the adress would be like 198.165.3.5 or some other collection of numbers. Once you set those numbers into the apps settings, relaunch vcdu and it will connect every time. Hope this wasn't too screwy of an answer for you.
Dave