so i've been trying to update my nexus one for the past two days and i couldn't do it, i'm on version 2.1 (i know my phone is very old ) but i fail each time i try to manually update it,
i've also tried updating it to 2.2 several times but it didn't work,
the problem was that when i click on "recovery" i dont get the /!\ sign instead it takes me to a page with some options like flash sd card, reboot now,
yeah i'm on build ERE36B i thought that this might be the problem but i don't know.

yeah i am the original owner and i never rooted it, i bought it 2 years ago and i used it for a few months and then stopped using it for a very long time

please help me, yeah excuse my english i'm not good at it and thank you