10.15.6 Security update install issue

[MacLawyer]

I just got my 2020 27" iMac. Upgraded the memory myself to 32 gigs. Then I was prompted to install the 10.15.6 security update. Every time I try, I get the black screen saying there was a problem and the computer had to restart. So no install has happened. I tried installing while the device was in safe mode, but had no luck. About this Mac shows the 32 gigs of RAM are indeed installed.

 

[Taz Mangus]

Remove the new RAM and install the old RAM and try the update.

 

[MacLawyer]

Taz, your suggestion worked! I may have forgotten that you need to install two 16 gig chips with one open slot between them. Going to run a chip test to rule out bad RAM. Thanks!

 

[Taz Mangus]

Glad it helped. Sometimes the simplest solution is the last thing we think of.

 

[MacLawyer]

Just ran Apple memory test (with the 32 gigs plugged back in). No issues. Weird. Thanks again.

 

[Kenjutsuz]

Remove the new RAM and install the old RAM and try the update.

From my past experiences,usually the last change you make to the OS/Hardware is the likely culprit.