I've been told USB on Unistream is a virtualized ethernet adaptor. I found that AVAST firewall was blocking USB connectivity but not ethernet when using my laptop on UniStream15.6. Turning third party firewall off allowed USB connection to work. This was on a laptop, Win 7 pro 64 bit. My discovery may not have any relevance to the issues being encountered o this thread but is an easy thing to try. I've also seen AVG FREE interfere with serial communucations to CAC card readers. Spent hours fidling with drivers to only find it's an AV problem.