Hey, I am having trouble pushing TWRP onto my op3 via fastboot. I managed to unlock my bootloader successfully but after that, I know cannot flash TWRP. When I type in "adb devices" It returns a string, however "fastboot devices" does nothing. I've uninstalled and re-installed oneplus usb, fastboot and adb drivers countless time and even reset my PC twice. Any ideas? This is really frustrating as I was on TWRP fine before I had to RMA my op3 where they put it back to stock. Any ideas? Thanks
Had the same issue, here's what fixed it for me:
(On Windows 10)
1 - Plug your device while on and install the OP3 drivers that appear as a removable disk, I reinstalled them also, so no harm in doing that again.
2 - Run admin command prompt from wherever you have your adb and fastboot
3 - get your device into fastboot/bootloader mode "adb reboot bootloader"
4 - press windows key + X and go to device manager, look for the Android device with exclamation mark
5 - right click on Android Device > update driver software > browse my computer... > let me pick... > look for Android and then select Android Fastboot Interface if memory serves me right.
And that's it. Fastboot should be recognized now. That's what worked for me when windows recognized adb but not fastboot, hope it helps out.
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