Hello
Please help
I have a late 2009 imac High Sierra 21.5" iMac i would like to use as a second monitor for my 2019 21.5" Retina iMac.
I have not been able to make the target display mode appear or even recognize each other. Is there a special adapter I am missing when trying to go from thunderbolt port to mini display.
The Late 2009 21.5” iMac will not work as a display for another Mac.
You need to have a Late 2009 27” iMac to use for Target Display Mode.
The Late 2009 21.5” iMac will not work as a display for another Mac.
You need to have a Late 2009 27” iMac to use for Target Display Mode.
Only 27" late 2009 iMac models will work in TDM and sorry there are no work arounds. Also, please note TDM was discontinued in 2015 (6 years ago now) and the final nail in the coffin was any Mac using Big Sur or later will not connect. Your best option is to buy an external display and use that. You will find this option the most simple, cost efficient and reliable solution.
Target Display Mode Problems; late 2009 to 2019
