The .fls file is the raw firmware data used to reprogram the printer's "brain." Applying this fix is typically done for two reasons:
: A stable USB cable connecting the printer directly to the PC. Do not use a wireless connection for firmware updates. Fix Ml1660 V1.01.00.30.fls
The process generally involves using a "USBPRNS2.exe" or "download.bat" tool to push the .fls file to the printer. Fix Ml1660 V1.01.00.30.fls
: Ensure the printer is set as the "Default" in your PC settings and the "Use Printer Offline" option is unchecked in the Windows Control Panel . Fix Ml1660 V1.01.00.30.fls