Problems turning of Target Display Mode on iMac

I'm connecting my macbook air to a late 2013 21.5inch iMac in target display mode, using the iMac as a display. The iMac works fine as a display, but when I try to turn target display mode off (command-F2, or unplugging the cable), the iMac screen goes black or fuzzy, and I can't use the iMac unless I restart it.

Any advice?

iMac 21.5", macOS 10.13

Posted on Jul 1, 2019 7:52 PM

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1 reply

rkaufmann87

Level 10

148,452 points

Jul 1, 2019 8:44 PM in response to troyashi63

Reset the NVRAM on both Macs per the directions in How to reset NVRAM on your Mac

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Problems turning of Target Display Mode on iMac

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