Hi friend if you're using windows open device manager and press v+ and connect phone then for just too small seconds a device with yellow attention icon appears in "unknown devices" part. You must right click on it as fast as you can before it disappears. Then in opened menu choose "update drivers" . choose "Browse my computer for driver software" and navigate to flashtool
Installation directory and choose driver folder then tap next. It must install fast boot drivers if it didn't you need to extract flashtool driver installer application in order to extract fast boot drivers using 7zip. Reply if you couldn't install to tell you how.
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