Until today I had no problem connecting my Mate 9 to my desktop and laptop PCs and being able to read the files on Mate 9 from my PC... The today "suddenly" it no longer was possible! I took the Mate 9 from one device to another around my house and couldn't read it on any of them.... UNTIL i realized that the one thing I did differently today than on any previous day was that today I used a generic USB cable instead of the cable that came from Huawei. THAT was the problem. Apparently there is special wiring in the Huawei cable that not only supports the Huawei Supercharging capability (when you use their charging brick) but also the wiring allows your PC to recognize the type of device and USB Device ID of your Mate 9. I had Huawei's HiSuite on both of my PCs and it didnt matter... THE CABLE was the problem!
If you dont have your original Huawei cable, they are available on Amazon. Here is the link to the item I bought from amazon to replace the original that began to fray. And NO I am not trying to sell anything. Just trying to help my fellow frustrated Huawei owners
https://www.amazon.com/gp/product/B0...cUvbUpU6575958
Amazon product/item ID B075TC5BZL