Xbox Series X Display is stuck on low resolution

Turned on the Xbox Series X this evening and the TV showed a very low resolution picture.

Symptoms

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Previous uses of the Xbox had been fine, but this time the display was small, blocky, and very low resolution even on the sign in page. Restarting the Xbox (including a full shutdown) and the television had no effect.

In the video settings for the Xbox the only choice was the selected 640x480 mode.

Solution

Check the HDMI cable between the console and the TV. In my situation I discovered the HDMI connector was not properly connected in the back of the Xbox and pushing it in correctly instantly returned the display to the proper resolution.