Problems with the Raspberry Pi Camera Module or HQ Camera are almost always fixed with one of the following solutions.
Important! Raspberry Pi OS Version
Following recent changes with the latest 'Bullseye' version of Raspberry Pi OS, you first need to determine which OS version you're using, as the camera works in very different ways depending on whether you're using Bullseye, Buster an earlier version.
How to check your Raspberry Pi OS Version
To find out what version you're currently running, open a terminal window and type cat /etc/os-release then hit enter.
You will see a line with 'VERSION_CODENAME=" and this will state "BULLSEYE", "BUSTER" or an earlier version.
If you're running Bullseye...
The #1 reason your camera may not appear to be working is probably because you're trying to use old commands such as raspistill and raspivid (or code libraries that make use of these).
Raspistill/Raspivid commands no longer work with the latest Bullseye release. Bullseye has moved to libcamera which means you'll need to use new commands. Unfortunately, the majority of articles on the internet will be out of date for some time.
A simple command to test that everything is working is libcamera-hello, which should show a 5-second camera preview on your connected monitor. More information on other command options can be found here.
Still not working? Check our other Camera Module Troubleshooting Tips.
Raspberry Pi Camera Module Troubleshooting Tips
Is your Camera set up and Installed? - Follow our setup guide
Camera Cable Connection - 90% of the time re-seating the cable fixes the problem (as the fiddly small cables only have to be slightly out to fail). Try removing and fitting the cable again.
Cable Direction - Another common issue where the metal part of the cable isn't round the right way which means there will be no connection at all. See our setup guide for pictures.
Is the Camera Enabled? - Have you checked that the camera is enabled in the raspi-config settings (sudo raspi-config)? (Not required in Bullseye)
Is your Software up to date? - Run 'sudo apt-get update' then 'sudo apt full-upgrade' in a terminal window to ensure your camera has the software it needs.
Are you using the most recent version of Raspberry Pi OS - Which is 'Bullseye' at the time of writing. If you're using 'Buster' or another previous version, you will need to reinstall the SD image, especially when using the HQ camera. Note that Bullseye uses libcamera commands, not raspistill/raspivid.
Reboot - Try rebooting your Pi if you've changed the camera/cable whilst it's switched on (we'd always recommend turning your Raspberry Pi off before switching the camera cable or any other hardware).
Operating System - Are you using the Raspberry Pi OS? The camera module is only officially supported by this operating system.
If your camera module is still showing no signs of life, please contact support.