Getting GetProp error that you don’t have the latest HHZ11k bootloader while installing a new custom ROM? This is due to the fact that some of the latest custom ROMs require the latest bootloader. You can unroot your Nexus 5 to the latest firmware to get the HHZ11k bootloader OR there’s a simpler way, just use fastboot to upgrade your bootloader manually. Step 1. To do this, simply put your Nexus 5 into bootloader mode (see video if you don’t know how).