Update : I now have rooted my ShieldTV but still, I am not able to delete any file on my usb drive or even on my internal SD card. I guess this is a marshmallow limitation but really, it drives me crazy.
I haven't rooted my shield yet thinking that it was a kitkat problem and that it had been solved with the 3.0 firmware..so I have no choice but to root it soon.
The fact is that I don't understand why the shield needs to be rooted to delete file...
I am in the same boat as you. When I bought my Shield with the 2.1 firmware installed, I did everything to delete files on my external USB hard drive from Kodi and I just couldn't. So I decided to root the Shield and from then I was finally able t...