The message "stream not loaded it might not be configured correctly or require authentication" appears under control in Octopi.
It may have appeared after I changed the flex cable between my Pi4 and the Raspberry HQ camera, OR when i replaced the mainboard on the printer to a btt skr mini e3 v2 (Did both upgrades in one go!)
I've tried changing the flexcable to one of the three cables I now have, but same happens with all of them.
How do i troubleshoot from here?
Systeminfo Bundle
browser.user_agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/90.0.4430.93 Safari/537.36
connectivity.connection_check: 8.8.8.8:53
connectivity.connection_ok: true
connectivity.enabled: true
connectivity.online: true
connectivity.resolution_check: octoprint.org
connectivity.resolution_ok: true
env.hardware.cores: 4
env.hardware.freq: 1500
env.hardware.ram: 3959984128
env.os.bits: 32
env.os.id: linux
env.os.platform: linux2
env.plugins.pi_support.model: Raspberry Pi 4 Model B Rev 1.2
env.plugins.pi_support.octopi_version: 0.17.0
env.plugins.pi_support.throttle_state: 0x0
env.python.pip: 19.3.1
env.python.version: 2.7.16
env.python.virtualenv: true
octoprint.safe_mode: false
octoprint.version: 1.5.3
printer.firmware: Marlin 2.0.7.2 (Dec 10 2020
Here's a list of troubleshooting things for you:
Try and open the stream URL in a separate tab on the browser window,
Find the webcamd logs using journalctl -u webcamd to find issues reported,
Run vcgencmd get_camera to see if the camera is detected by the Pi,
And that's it for now I think. Let us know how you get on 
Thanks.
Here are the results;
pi@octopi:~ $ journalctl -u webcamd
-- Logs begin at Tue 2021-04-27 22:17:01 BST, end at Sun 2021-05-02 12:25:16 BST
Apr 27 22:17:04 octopi systemd[1]: Starting the OctoPi webcam daemon with the us
Apr 27 22:17:05 octopi webcamd[371]: Starting up webcamDaemon...
Apr 27 22:17:05 octopi webcamd[371]: --- Configuration: ------------------------
Apr 27 22:17:05 octopi webcamd[371]: cfg_file: /boot/octopi.txt
Apr 27 22:17:05 octopi webcamd[371]: camera: raspi
Apr 27 22:17:05 octopi webcamd[371]: usb options: -r 640x480 -f 10
Apr 27 22:17:05 octopi webcamd[371]: raspi options: -x 1280 -y 720 -fps 10
Apr 27 22:17:05 octopi webcamd[371]: http options: -w ./www-octopi -n
Apr 27 22:17:05 octopi webcamd[371]: Explicitly USB device:
Apr 27 22:17:05 octopi webcamd[371]: -------------------------------------------
Apr 27 22:17:05 octopi webcamd[371]: Found video devices:
Apr 27 22:17:05 octopi webcamd[371]: /dev/video10
Apr 27 22:17:05 octopi webcamd[371]: /dev/video11
Apr 27 22:17:05 octopi webcamd[371]: /dev/video12
Apr 27 22:17:05 octopi webcamd[371]: /dev/video13
Apr 27 22:17:05 octopi webcamd[371]: /dev/video14
Apr 27 22:17:05 octopi webcamd[371]: /dev/video15
Apr 27 22:17:05 octopi webcamd[371]: /dev/video16
Apr 27 22:17:05 octopi webcamd[371]: Scan again in two minutes
Apr 27 22:29:20 octopi systemd[1]: webcamd.service: Start operation timed out. T
Apr 27 22:29:20 octopi webcamd[371]: /root/bin/webcamd: line 103: kill: (456) -
Apr 27 22:29:20 octopi webcamd[371]: Goodbye...
lines 1-23...skipping...
-- Logs begin at Tue 2021-04-27 22:17:01 BST, end at Sun 2021-05-02 12:25:16 BST. --
Apr 27 22:17:04 octopi systemd[1]: Starting the OctoPi webcam daemon with the user specified config...
Apr 27 22:17:05 octopi webcamd[371]: Starting up webcamDaemon...
Apr 27 22:17:05 octopi webcamd[371]: --- Configuration: ----------------------------
Apr 27 22:17:05 octopi webcamd[371]: cfg_file: /boot/octopi.txt
Apr 27 22:17:05 octopi webcamd[371]: camera: raspi
Apr 27 22:17:05 octopi webcamd[371]: usb options: -r 640x480 -f 10
Apr 27 22:17:05 octopi webcamd[371]: raspi options: -x 1280 -y 720 -fps 10
Apr 27 22:17:05 octopi webcamd[371]: http options: -w ./www-octopi -n
Apr 27 22:17:05 octopi webcamd[371]: Explicitly USB device:
Apr 27 22:17:05 octopi webcamd[371]: -----------------------------------------------
Apr 27 22:17:05 octopi webcamd[371]: Found video devices:
Apr 27 22:17:05 octopi webcamd[371]: /dev/video10
Apr 27 22:17:05 octopi webcamd[371]: /dev/video11
Apr 27 22:17:05 octopi webcamd[371]: /dev/video12
Apr 27 22:17:05 octopi webcamd[371]: /dev/video13
Apr 27 22:17:05 octopi webcamd[371]: /dev/video14
Apr 27 22:17:05 octopi webcamd[371]: /dev/video15
Apr 27 22:17:05 octopi webcamd[371]: /dev/video16
Apr 27 22:17:05 octopi webcamd[371]: Scan again in two minutes
Apr 27 22:29:20 octopi systemd[1]: webcamd.service: Start operation timed out. Terminating.
Apr 27 22:29:20 octopi webcamd[371]: /root/bin/webcamd: line 103: kill: (456) - No such process
Apr 27 22:29:20 octopi webcamd[371]: Goodbye...
Apr 27 22:29:20 octopi systemd[1]: webcamd.service: Failed with result 'timeout'.
Apr 27 22:29:20 octopi systemd[1]: Failed to start the OctoPi webcam daemon with the user specified config.
Apr 27 22:29:20 octopi systemd[1]: webcamd.service: Service RestartSec=100ms expired, scheduling restart.
Apr 27 22:29:20 octopi systemd[1]: webcamd.service: Scheduled restart job, restart counter is at 1.
Apr 27 22:29:20 octopi systemd[1]: Stopped the OctoPi webcam daemon with the user specified config.
Apr 27 22:29:20 octopi systemd[1]: Starting the OctoPi webcam daemon with the user specified config...
Apr 27 22:29:20 octopi webcamd[799]: Starting up webcamDaemon...
Apr 27 22:29:20 octopi webcamd[799]: --- Configuration: ----------------------------
Apr 27 22:29:20 octopi webcamd[799]: cfg_file: /boot/octopi.txt
Apr 27 22:29:20 octopi webcamd[799]: camera: raspi
Apr 27 22:29:20 octopi webcamd[799]: usb options: -r 640x480 -f 10
Apr 27 22:29:20 octopi webcamd[799]: raspi options: -x 1280 -y 720 -fps 10
Apr 27 22:29:20 octopi webcamd[799]: http options: -w ./www-octopi -n
Apr 27 22:29:20 octopi webcamd[799]: Explicitly USB device:
Apr 27 22:29:20 octopi webcamd[799]: -----------------------------------------------
Apr 27 22:29:20 octopi webcamd[799]: Found video devices:
Apr 27 22:29:20 octopi webcamd[799]: /dev/video10
Apr 27 22:29:20 octopi webcamd[799]: /dev/video11
Apr 27 22:29:20 octopi webcamd[799]: /dev/video12
Apr 27 22:29:20 octopi webcamd[799]: /dev/video13
Apr 27 22:29:20 octopi webcamd[799]: /dev/video14
Apr 27 22:29:20 octopi webcamd[799]: /dev/video15
Apr 27 22:29:20 octopi webcamd[799]: /dev/video16
Apr 27 22:29:20 octopi webcamd[799]: Scan again in two minutes
Apr 27 22:30:50 octopi systemd[1]: webcamd.service: Start operation timed out. Terminating.
Apr 27 22:30:50 octopi webcamd[799]: /root/bin/webcamd: line 103: kill: (810) - No such process
pi@octopi:~ $ vcgencmd get_camera
supported=1 detected=0
I'm guessing the last one indicates that the camera si not detected by the pi?
Faulty camera...?
Correct. Check the ribbon cable, and also the ribbon that attaches the sensor to the camera module. Not familiar with the HQ cam to see how it works there.