I have a E7240 that is approx 1 yr old and now acting up with some of my USB devices. I have a Polycom CX100 speaker that used to work flawlessly whenever I had it plugged into the laptop undocked or docked. About a week ago I started to get the USB Device Not Recognized error message when I plugged it in. It happened both when docked and undocked. I thought the Polycom died so I ordered another one.....same problem. Well, I spent countless hours reading online and still have issues. I have upgraded BIOS, taken the battery out, deleted everything out of device manager, power up, power down, check BIOS settings, run Microsoft fixit tools, etc and still no luck.
The only way I got it to work was to plug it into the side USB port rather than the back USB ports (I'd testing undocked right now)! I normally use the side USB for my Logitech USB mouse but unplugged it to troubleshoot. Low and behold my Polycom speaker worked in the side port. I plugged it into the back ports (still undocked) and get the all too familiar "USB device not recognized" error message.
So, how can I get the back USB ports working and why does there seem to be a different response from side vs. back ports? I need them to work when undocked then I can tackle getting it to work when docked. Incredibly frustrating Dell.
Any more troubleshooting ideas would be greatly appreciated.
Thank You
