iMac blue screen

Can anyone tell me what is happening here, please? My iMac often 'sleeps' with this screen and is very slow to wake. There are no issues with starting up. Hitting the escape key usually returns the normal login screen. I have reinstalled Mac OS but the problem persists.

It's a late 2015 27" iMac with 5K Retina display running Catalina 10.15.5.

iMac Line (2012 and Later)

Posted on Jun 21, 2020 10:26 PM

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4 replies

rkaufmann87

Level 10

148,494 points

Jun 21, 2020 10:39 PM in response to richardjfraser

Please reset the NVRAM and also restart in Safe Mode and then. restart normally and retest.

How to reset NVRAM on your Mac

Use safe mode to isolate issues with your Mac

Jun 21, 2020 11:55 PM in response to rkaufmann87

Thanks - I'll try it.

Jun 23, 2020 8:00 PM in response to rkaufmann87

It has worked - many thanks!

rkaufmann87

Level 10

148,494 points

Jun 23, 2020 10:09 PM in response to richardjfraser

Your welcome.

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iMac blue screen