Mode not supported error message

Hello DeeDee335,

Thanks for using the Apple Support Communities!

I understand that you have run into an issue where your Apple TV is no longer connecting to your TV as you would expect. I can also see that you have already tried some great troubleshooting.

To continue the troubleshooting process, I suggest reading over and working through the steps located in the following article.

If you have video issues or see an HDCP alert

Find out what to do for your particular issue, like blank or distorted screens, HDCP alerts, aspect ratios, and color issues.

If you see issues like an HDCP alert or a blank, flickering, or static screen

1. Unplug both ends of your HDMI cable. Then firmly plug them back in.
2. Turn off your TV and receiver (if you use one). Unplug your Apple TV from power, then plug it back in. Turn your receiver and TV back on.
3. In your TV's menu, make sure that you select the HDMI input that matches the HDMI port connected to your Apple TV. Check your TV's manual for help.
4. Connect your Apple TV directly to your TV instead of using a receiver or HDMI switch, since the issue might be with your receiver or switch.
5. Try a different HDMI cable to see if the issue is with your cable.

If you need more help with video issues, try adjusting the HDMI and display settings on your Apple TV. Go to Settings > Audio and Video. If the screen is blank and you can’t go to Settings, you can use your remote to change the resolution:

1. For Apple TV (4th generation), hold Menu and Volume Down for five seconds. For Apple TV (2nd or 3rd generation), hold Menu and Up for five seconds.
2. After you let go of the buttons, your Apple TV will switch to a new resolution every 20 seconds. Select OK to choose a resolution. Select Cancel to quit.

Get help with audio, video, or power on Apple TV - Apple Support

Cheers!

Post a picture of the screen message and the Model number of your TV.