I have a 2009 IMAC. I am trying to use it as a dual monitor with my new 2019 IMAC. I purchased the proper cords, thunderbolt three to two adapter. I connected the video port to the proper adapter. Following the above command 2 and cmd fn 2
Can anyone help me diagnose my problem? I have a 2009 (late) Imac running high Sierra 10.13.6. I have tried all the suggestions to use it as a dual monitor with my 2019 IMAC. Nothing has worked. I have tried all the troubleshooting suggestions with no results. There's no indication that the two computers are connected. Can anyone suggest other options?
iMac 21.5″, macOS 11.5