adb sideload does not transfer data Just to clarify, it's my first time trying to unlock and root my phone, so I'm not very knowledgeable in this matter.

I basically followed the steps to unlock the bootloader.

Everything worked perfectly, I reached the recovery, went on 'apply update from ADB'. 

But then, when I enter in cmd,

adb sideload 'whatever the filename


it prints out the Android Debug Bridge instructions on cmd rather than transferring the zip file to my phone, and the phone keeps on asking "now send the package you want to apply to the device with adb sideload filename ".

N.B.: the phone is recognized by adb, even when I enter adb devices, it is recognized.

Any help would be appreciated.
adb sideload does not transfer the file to the sdcard permanently. To sideload correctly, you need to pick that option from the recovery first and then when the phone is waiting for the sideload type,

adb sideload &lt;PACKAGE&gt;


If you want to push the file to the phone's sdcard, you could try,

adb push &lt;PACKAGE&gt; /sdcard/


That should copy the file over to the sdcard. Keep in mind that there is no progress bar.

EDIT: Try the following to restart the adb server,

adb kill-server


then,

adb start-server


Then check if the instructions work again.