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                  1. Support
                  2. Prusa CORE One+
                  3. Printer maintenance
                  4. How to downgrade firmware (CORE One/+, MK4/S, MK3.9/S, MK3.5/S, XL)
                   

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                  How to downgrade firmware

                  (CORE One/+, MK4/S, MK3.9/S, MK3.5/S, XL)

                  Relevant for

                  CORE One family
                  MK4 family
                  XL family
                  MK3.9 family
                  MK3.5 family
                  16 comments
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                  Sometimes it is necessary to reinstall an older version of the firmware. The method to update the firmware only allows newer firmware versions to be flashed. To flash the same firmware, or an older one, follow the steps below.

                  If it repeatedly only boots the printer and gives you the home screen, try to format your USB flash-drive or try a different one. Even if the flash drive works with G-Codes and printing, it may not work for flashing the firmware.
                  1. To find the older versions, go to the Downloads page, select your printer, and click on Older versions.

                  1. Load the .bbf file directly into the root folder of the USB drive.
                  2. Insert the drive into the printer.
                  3. Push the reset button, and once the printer logo appears on the screen, press the display knob once.
                  4. On the new screen, confirm the update by selecting the "FLASH" button and pressing the display knob.

                  Factory Reset

                  If you do a hard Factory Reset, the firmware that is in the USB will also be installed in the printer, so this can be used as a way to update the firmware.

                  Was this article helpful?
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                  10 comments

                  Log in  to post a comment
                  Y arno
                  •
                  Obligé de downgrader au 6.4.0, car MMU en défaut sur le dernier Firmware, Pfoouuu.
                  Je confirme -> 2 Clics sur le bouton, une fois le logo affiché !!!!!!!!
                  Reply
                  JCHH
                  •
                  I had the problem of repeatedly booting to the home screen (blue box above).

                  I found that simply deleting the hidden files on the thumb drive was enough (no need to reformat.
                  Reply
                  SF_Gizmo
                  •
                  Single click worked for me.
                  Reply
                  Service Velo 63
                  •
                  2 clicks activate the firmware update
                  Reply
                  yvan levasseur
                  •
                  wow.. that is some corection that need to be adress.
                  with out tis info i will never be able to set my mmu..
                  I all ready spent to many hours to set up...
                  25h..
                  that is not acettable
                  Reply

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