Octoprint refuses to connect with Ender 3

What is the problem?

I try to connect my Ender 3 printer to OctoPrint and it refuses to connect.

What did you already try to solve it?

I have tried many different ports, updating drivers, using different drivers, updating bit rate, pretty much everything I could find.

Have you tried running in safe mode?

No I don't get how to run it in safe mode, I dont think this would solve the problem anyways as I have tried in two other slicers and they have refused to connect as well.

Did running in safe mode solve the problem?

Did not try.

Systeminfo Bundle

You can download this in OctoPrint's System Information dialog ... no bundle, no support!)

octoprint-systeminfo-20220224213508.zip (19.9 KB)

Changing monitoring state from "Offline" to "Detecting serial connection"
Performing autodetection with 7 port/baudrate candidates: COM7@115200, COM7@250000, COM7@230400, COM7@57600, COM7@38400, COM7@19200, COM7@9600
Trying port COM7, baudrate 115200
Connecting to port COM7, baudrate 115200
Handshake attempt #1 with timeout 2.0s
Connected to: Serial<id=0x24fb1ca0460, open=True>(port='COM7', baudrate=115200, bytesize=8, parity='N', stopbits=1, timeout=2.0, xonxoff=False, rtscts=False, dsrdtr=False), starting monitor
Send: N0 M110 N0*125
Handshake attempt #2 with timeout 2.0s
Send: N0 M110 N0*125
Handshake attempt #3 with timeout 2.0s
Send: N0 M110 N0*125
Trying port COM7, baudrate 250000
Handshake attempt #1 with timeout 2.0s
Send: N0 M110 N0*125
Handshake attempt #2 with timeout 2.0s
Send: N0 M110 N0*125
Handshake attempt #3 with timeout 2.0s
Send: N0 M110 N0*125
Trying port COM7, baudrate 230400
Handshake attempt #1 with timeout 2.0s
Send: N0 M110 N0*125
Handshake attempt #2 with timeout 2.0s
Send: N0 M110 N0*125
Handshake attempt #3 with timeout 2.0s
Send: N0 M110 N0*125
Trying port COM7, baudrate 57600
Handshake attempt #1 with timeout 2.0s
Send: N0 M110 N0*125
Handshake attempt #2 with timeout 2.0s
Send: N0 M110 N0*125
Handshake attempt #3 with timeout 2.0s
Send: N0 M110 N0*125
Trying port COM7, baudrate 38400
Handshake attempt #1 with timeout 2.0s
Send: N0 M110 N0*125
Handshake attempt #2 with timeout 2.0s
Send: N0 M110 N0*125
Handshake attempt #3 with timeout 2.0s
Send: N0 M110 N0*125
Trying port COM7, baudrate 19200
Handshake attempt #1 with timeout 2.0s
Send: N0 M110 N0*125
Handshake attempt #2 with timeout 2.0s
Send: N0 M110 N0*125
Handshake attempt #3 with timeout 2.0s
Send: N0 M110 N0*125
Trying port COM7, baudrate 9600
Handshake attempt #1 with timeout 2.0s
Send: N0 M110 N0*125
Handshake attempt #2 with timeout 2.0s
Send: N0 M110 N0*125
Handshake attempt #3 with timeout 2.0s
Send: N0 M110 N0*125
Changing monitoring state from "Detecting serial connection" to "Error"
Changing monitoring state from "Error" to "Offline after error"
Connection closed, closing down monitor

Additional information about your setup

OctoPrint version, OctoPi version, printer, firmware, browser, operating system, ... as much data as possible

Windows 10 64 bit, Ender 3, Lastest Ender 3 firmware as far as I can tell, (I was using Cura USB connections when that suddenly stopped working) OctoPrint 1.7.3, Chrome, Python 3.10.2

Please let me know what extra information I can provide and how to find it!

Were cura or other slicers running while you tried to connect to the printer?
They might block the port.

@PrintedWeezl I read about that, I made sure to close Cura and uncheck USB printing in Cura.

@PrintedWeezl I hope im not bothering you, have you thought of any solutions?

Sry didn't have any new ideas

You could test it with another software like pronterface or on another device (like a laptop) to rule out your pc.

Also try it with a different cable.. I's unlikely but maybe the cable broke

Tried those, I have a spare motherboard for the printer, I feel that the motherboard is causing the problem.

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