While the "unknown request-firmware updater preflight-" error sounds intimidating, it is rarely a sign of hardware failure. It is almost always a communication breakdown
On Chromebooks or IoT devices, this appears when the update_engine attempts to verify firmware rollback protection.
The firmware updater received a request that it does not recognize during the preflight (pre-update validation) phase. The hyphen indicates additional details were truncated.
Have you seen this message on a non-standard device? Drop the details in the comments. unknown request-firmware updater preflight-
The phrase unknown request-firmware updater preflight- can be split into four key tokens:
Let’s break it down.
: Verify that the firmware file is not corrupted and is complete. Sometimes, re-downloading the firmware file can resolve the issue. The hyphen indicates additional details were truncated
Thus, unknown request-firmware updater preflight- is likely a minor variant of these known patterns.
If you see this message in a log file ( /var/log/syslog , /var/log/messages , dmesg , Windows Event Viewer, or a serial console), follow this systematic approach:
: You can bypass the graphical interface by forcing the update through the command line. Open softwareupdate -i -a Windows Event Viewer
The best text for a firmware updater preflight depends on whether this is an internal log or a message for an end-user. For End-Users (Clear & Safe)
: Switch from Wi-Fi to Ethernet if possible, or simply toggle your Wi-Fi off and back on to refresh the connection to Apple's SUS (Software Update Servers). Reset NVRAM/PRAM