Hi everybody,
Just to share that I had this issue, I searched for solution and I found this thread
https://answers.microsoft.com/en-us/windows/forum/all/camera-app-shows-error-0xa00f4244/1770cf83-6fe4-4763-83cf-70a13f38e4a7?from=GetHelpBCQR&CorrelationId=e59a86a8-68a4-45bf-8dd5-2c6dace14574&ocid=OO_Core_NEU_GetHelp_DG_GetHelp_Solutions
and to the 3 solutions presented by DaveM121 I would add this one:
4
Check if any video conferencing software has any pending update.
In my case, it was zoom.
I updated, rebooted and then, since the camera was not active, I repeated #1 from the mentioned thread
1
Look at the function keys (F1 - F12) on your keyboard, if one of them has a camera icon, press that key or Fn + that key to unlock the webcam.
and voila!
Everything's working!!
In my case was Fn + F6.
I hope this has been helpful, as this problem appears quite regularly...