Hello .... please advice! ... I'm new to Android and just bought a used Nexus One... I always get a notice for system upgrade saying: Android Update (part 1 of 2) telling that this first part is required to prepare my device to receive new Android system software, and that my device will restart and my settings and data will be preserved and soon thereafter I will receive the second update containing the new Android system software itself. After clicking the Restart and Install... I'm getting the following screen and not sure what to choose as I said I'm not familiar with such system upgrades: Android system recovery - Reboot system now. - USB – MS toggle. - Flash zip from sdcard. - Wipe. - Partition sdcard. - Other. - Power off. Build: RA-Nexus – v1.5.3 Finding update package… Opening update package… Verifying update package… E: No signature (8 files) E: Verification failed Installation aborted Note that my Android version is 2.2 and Build number is FRF50. Please Advice what to choose and what steps should I follow later! Sorry for my long post! Many Thanks.