Thanks for your replies guys.
I never extracted it. I downloaded, then renamed to update.zip, copied to SD card in phone and tried to update from recovery mode.
It was the same process I used before to manually update to 3.87 or whatever it was called.
What else should I try? Pls help.
Btw could there be leftover files on the sd card from last manual update that's causing this?
PS I even downloaded file again but still same message.
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