Not detecting external monitor

Since upgrading my software, my iMac is not detecting my external monitor. I've tried shutting down, putting it in sleep mode, unplugging adapter & powering off monitor. The monitor works fine on my old macbook pro, which was not upgraded.

Are there issues with MacOS Big Sur?

iMac 21.5″, macOS 11.0

Posted on Nov 16, 2020 7:42 AM

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Not detecting external monitor

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