can't open open

[EJT501]

i am trying to download the update.zip (2.0.1) ive done everything but before i even go to apply it pops up with

E:Can't open /cache/recovery/command

then after i try to apply it makes it to installing update but then it says

E:Error in /sdcard/update.zip

is there anything that can be done?
i really wanna update it so i can root it.