I believe it's simply the pull-up resistor on the D- line that causes Windows to detect you have plugged something in.
Check you have the D+ and D- lines the right way round - the correct colour coding is in Wikipedia, but the first Google hit for the image search has the green and white reversed (or it did when I looked).
Check you have the D+ and D- lines the right way round - the correct colour coding is in Wikipedia, but the first Google hit for the image search has the green and white reversed (or it did when I looked).