There are several known reasons why this error is coming up. Read and follow one step at a time and correct it as you go. This means to follow one step and do a test, if it prompts you again, move on to the next method to troubleshoot.
You did not turn the camera on first, then the software
In later updates of the software it became necessary to turn on the camera first, then the software. Not doing so results in errors such as this. Turn off the booth, turn off the camera. Turn on the booth, turn on the camera, open the software and you will be in the clear for this simple step.
EOS software was installed, photoshop was installed or other Adobe platform was installed and is running.
This error means that the camera could not talk to the software. If EOS software is running (software that talks to the camera) it will not allow the program to do what it needs to. Other programs running Adobe can also take over processes that Social Booth rely on. Bring up the task manager and make sure they are not running.
Camera settings reset needs to occur
One or more camera settings may have been changed. In this kind of case, it is most important to start over from scratch.
Locate the "Reset camera settings" within the camera menu. Each camera is different, but you will need to locate that setting, it is typically in the far right of the camera settings.
Once the camera settings have been wiped. Please follow this (WITHOUT THE TABLET ON):
1. CAMERA DIAL ON M (MANUAL)
2. ZOOM LENS TO 24MM
3. LENS TO MF AND STABILIZER OFF
4. AF on
5. TURN CAMERA ON (NOT ON VIDEO MODE some cameras may have a video setting after being turned on, make sure it is set to on and not on Video Mode )
Then watch this video at the 6:50 mark:
AF Operation: AI Servo
Once the settings are reset, make sure the AI servo setting is set, the default is One Shot and that will cause problems.
If you still have problems:
Check the lens and set it from AF to MF. If it works, that means either AI Servo is not set within the camera or the lens is going out. This is the very first thing you can do to best help. Setting the lens to MF is a quick fix to the problem.
Replace the camera data cable, does it still have a problem? Buy one here if you don't have a backup.
Replace the USB hub, buy one here if you need a backup.
Still having issues? Try swapping the camera with a camera you may have lying around or just change the lens. If a lens swap made the error go away, the lens was suffering hardware failure with the application.