Windows 10 device descriptor request failed

Yesterday I encountered the error in the post title when moving my StarTech 4 Port USB to Serial Adapter from a 10 year old PC (that finally died) to my current engineering workstation. I’d never experienced that particular error before so I Googled it and read about a dozen articles with suggestions for fixing it and none of them helped.

Being an engineer of electronic instruments I realized I needed to step back, assume nobody posting on the internet really has a full grasp of how USB works, and think about the system and how to methodically troubleshoot the problem. I soon realized that I’d skipped what should always be the first tests, cables. I have the USB/Serial box mounted at the test bench and it’s connected via a long USB cable and extension back to my workstation. To make a long story short, I learned that this device is less tolerant of using excessively long (out of spec long) USB cables than other USB 2.0 devices I use. For convenience I was using an existing run that made the total distance 8 meters. Swapping the 4.5 meter extension cable for a 2 meter extension cable fixed the problem.

BTW – looking back on this problem where I wasted at least an hour of my time I noticed there was a clue on the product page. The Accessories tab lists one single item, 15 ft USB 2.0 Active Extension Cable.