I got close to getting VDS Pro to work with my USB cable in Win 7 today...
I've done a lot of trial and error and haven't quite gotten it to work yet. Here's what I've done thus far:
First, you need different drivers from Ross-Tech for your USB cable. That can be found
here. This makes it so that your Ross-Tech USB cable can be recognized by other programs who would use the cable via COM/serial port.
Follow the instructions closely at the above link.
The next thing I did was download
DOSBox.
This isn't only a DOS Emulator, but an x86 emulator. It even has control to virtually vary the processing speed since some programs expect to see specific processor speeds to work correctly. Some programs may run too fast or slow depending what it's set at. This isn't something we need to be concerned with using VDS pro, however. Just a general idea of some of the things DOSBox is capable of.
I put VDS Pro in c:\vds_pro\ on my PC. Once DOSBox is started, you need to mount a virtual C:. The prompt defaults to Z:\.
To do this, you enter: mount c c:\vds_pro
Or at least that's what I did for my case since that's where the files I am concerned with are located.
You then give the command to change drives: c:
Enter the name of the bat file to start VDS Pro: vag
VDS Pro starts up, no problem. At first I get a UART error due to the cable not being hooked up. My cable was set in Windows to COM3. I manually changed the setting in VDS Pro to use the cable on COM3. The error went away and it appeared to attempt to connect. Hook it up to a car with the key on, nothing. The LED on the cable doesn't even turn red at any point. Just stays green.
I've tried a number of different things, even putting the VCDS cable to COM1 and completely reinstalling VDS. It still won't communicate.
Also of note, there is a command you can use to virtually map whatever com port you want to be recognized as com1 or 2 etc. in DOSBox. Before changing my cable to COM1 in Windows, I attempted to map COM3 to COM1 in DOSBox and all I got were error codes in the status screen.
Close, but no cigar! It was also suggested to me to uncheck the "start in smart mode" box in VCDS. No change.
Would be curious to see someone else give it a go.