To bypass this “No Signature, Verification Failed Error”, you must install ClockworkMod Recovery image
How to Bypass Android No Signature, Verification Failed Error
By Ben Johnson last updated February 7, 2012
Share on TwitterShare on Google+Share on FacebookShare on LinkedInYesterday i received Android 2.2.1 (FRG83) update (signed-passion-FRG83-from-FRF91.c8847c98.zip) on my Nexus One OTA. Before applying the update, my Nexus One was running Android 2.2 (FRF91) which was rooted using 1-click Universal Androot utility. Only applying the update via stock Android system recovery, i got “No Signature, Verification Failed Error” error.
After installing Amon_Ra’s Recovery image and downloading the (FRG83) update manually, i tried to install the update.zip via Amon_Ra’s Recovery but unfortunately again got the same “No Signature, Verification Failed Error” error.
*Above image is for illustration purpose only
Finding update package…
Opening update package…
Verifying update package…
E:No signature (188 files)
To bypass this “No Signature, Verification Failed Error”, you must install ClockworkMod Recovery image.
•Start your Android phone normally and place update.zip in the root of your SD card.
•Go to Android Market, search for ClockworkMod, select ROM Manager from the list and install it.
•Once you have installed the ROM Manager, launch ROM Manager and grant Superuser Permissions to it.
•Click on Flash ClockworkMod Recovery to install ClockworkMod Recovery image.
•Choose Reboot into Recovery and ROM Manager will boot you to recovery mode.