Basic Information: Printer Model: Ender 3 V2 MCU / Printerboard: V 4.2.2. on Raspberry Pi 4 klippy.log (158.4 KB) Hello, after updating Klipper was unable to connect to the MCU. (It was working fine before updating) I reinstalled Klipper and the problem stayed or is even worse: [image] I h…

Thank you,I have tried the solution now. But it didnt work for me. Seems like im affected with the bug of version “247.3-7+deb11u2”. I added the source and installed it after fixing the Error with the public signing keys.

Make sure you followed the instructions to the letter. In doubt, re-check / repeat. Post the output of apt-cache policy udev

Okay i have repeated the process. The output of apt-cache policy udev looks like this: udev: Installed: 252.5-2~bpo11+1 Candidate: 252.5-2~bpo11+1 Version table: *** 252.5-2~bpo11+1 100 100 Index of /debian bullseye-backports/main armhf Packages 100 /var/lib/dpkg/status 247.3-7+rpi1+de…

My problem is now solved. I have followed a couple post. Seems like https://klipper.discourse.group/t/ender-3-s1-no-usb-id/8120/5?u=rbk fixed my issue. But im not very sure

Ender 3 V2 - MCU cannot be found

General Discussion

Sineos July 14, 2023, 7:41pm 2

See Debian Bullseye Bug causing Klipper to no longer find the printer board

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Ender 3 V2 - MCU cannot be found

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