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sykes1987 Author

Level 1

4 points

My LG monitor is connected to my iMac but it cannot be detected.

I have an iMac (Retina 4K, 21.5-inch, 2017) and I am trying to connect an external 4k LG monitor 24UD58.

It is connected via a USB C to HDMI adaptor (the apple one).

No matter what I try the iMac doesn't detect the monitor. I have tried restarting with all connected, powering up and connecting etc etc. I have tried detect displays but nothing is found.

I have tried all cables and monitor with my MacBook Pro and it works with no issues so I know the issue if coming from my iMac, anyone else had this issue and know a fix?

Posted on Feb 2, 2021 1:04 AM