cant upgrate my phone

hi
i'm trying to upgrate my htc one m8 verizon fom htc synxc manager because i'm outside us but whet it starts t upgrate my phone shuts down ang goes to fastboot usb and my conpiuteer says disconected and cant upgrate. can anyone gime any solution please

starting up after upgrate

hi guys!!

after i upgraded my z2, it starts until the (SONY XPERIA) finishes then it just restart again... i tried to upgrade it manytimes with different firmwares... but still same result... plz help!!!

my original was l50u- v4.4.2 chinese


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