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                  1. Support
                  2. Printer troubleshooting
                  3. Invalid FW size on USB #12603 (MINI/MINI+)
                   

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                  Invalid FW size on USB

                  #12603 (MINI/MINI+)

                  Relevant for

                  MINI
                  MINI+
                  Article is also available in following languages
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                  What happened?

                  While flashing firmware to your printer an error might occur, and the screen will display the following message: "Firmware file has invalid size! Check the file on the USB drive and try again".

                  Error name: Invalid FW size on USB

                  Error code: #12603

                  This error can happen if the bootloader file is edited, or if the USB is removed from the computer before the end of the file transfer.

                  How to fix it? 

                  Delete both files from the USB drive, and download them again. Transfer the files to the USB drive. Make sure to unmount the drive from your operating system before physically removing it. This will prevent the USB drive from being removed too early.

                  Insert the USB drive back into the printer and restart it to initiate the flashing procedure. In case the procedure does not start, reboot the printer using the reset button directly next to the knob and while the printer is booting up, press once the rotating knob (more about this on alternative method).

                  If the issue persists, the problem might be in the USB flash drive. Find any other USB drive in your household, make sure it is formatted to FAT32, copy both firmware files and repeat the previously described procedure.

                  Are you still having issues? Contact our support team and let them know, that you have tried to fix the issue with these instructions. We will take it from there.

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                  Topics

                  • Troubleshooting
                    • Printer troubleshooting
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                      • Maxtemp error bed #12205 (MINI)
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                      • Temp not matching print head #12210 (MINI/MINI+)
                      • PrusaLink Troubleshooting
                      • Homing Error #12301 (MINI)
                      • USB not connected #12602 (MINI/MINI+)
                      • No file on USB #12604 (MINI/MINI+)
                      • Signature verification failed #12606 (MINI/MINI+)
                      • Hash verification failed #12607 (MINI/MINI+)
                      • Unsupported printer type #12610 (MINI/MINI+)
                      • Unsupported printer version #12611 (MINI/MINI+)
                      • Flash erase error #12605 (MINI/MINI+)
                      • Temp not matching heatbed #12209 (MINI/MINI+)
                      • No FW in internal flash #12612 (MINI/MINI+)
                      • Invalid FW size on USB #12603 (MINI/MINI+)
                      • File system error #12613 (MINI/MINI+)
                      • Unsupported BBF version #12614 (MINI/MINI+)
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                      • Emergency stop #12510 (MINI)
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