Depending on your authorization level and the urgency of the issue, there are several approaches to resolve the "flashing lock flag is locked" error.
This is the most common scenario for this specific error text. flashing lock flag is locked please unlock it first full
Here's a helpful breakdown of what that means and how to resolve it. Depending on your authorization level and the urgency
Newer USB 3.0/3.1 ports (blue or red) sometimes cause timing issues with Fastboot. Try a USB 2.0 port if available. flashing lock flag is locked please unlock it first full
The error message "Flashing Lock Flag is locked. Please unlock it first!"
Turn off your CNC machine and the controller board (e.g., Arduino Uno with GRBL). Wait 10 seconds. Power back on. This clears the volatile lock flag memory.