if you happen to have a old new matter mod t printer that's still working. I've recently run into an issue that I haven't encountered yet. where periodically the filament header who climb all the way up to the very top of the lead screw and it causes an issue on future prints. when I connect via USB cord, the printer power light flashes on and off and my computer will not recognize that it's connected. this is a really quick video on the fix that I found where all you need to do is use the thread setting on the back to lower the top filament mount off of the very top setting and you should be back in business.