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january01smith
Participant
August 17, 2020
Answered

Error installing LR4 - digital signature is not trusted

  • August 17, 2020
  • 3 replies
  • 1599 views

Trying to install my old 4.0 version of Lightroom on my macBook Air and receive the error:  "Adobe Photoshop Lightroom 4.pkg can’t be installed because its digital signature is not trusted."

 

I have searched other posts and tried a few suggestions but have not been successfull.

 

Any  ideas?

This topic has been closed for replies.
Correct answer GoldingD

While LR v4 may be a 64bit app, the installer is not. The installer is 32bit.

 

You can not run a 32bit app in Catalina.

 

3 replies

TheDigitalDog
Inspiring
August 17, 2020

Boot into an older OS that CAN support a 32-bit installer (like Mojave), install, then you should be able to run LR, at least I can run LR5, under Catalina. LR4? Maybe, maybe not. 

Author “Color Management for Photographers" & "Photoshop CC Color Management/pluralsight"
GoldingD
GoldingDCorrect answer
Legend
August 17, 2020

While LR v4 may be a 64bit app, the installer is not. The installer is 32bit.

 

You can not run a 32bit app in Catalina.

 

AxelMatt
Community Expert
Community Expert
August 17, 2020

Which version of MacOS is running on your MacBook?

 

My System: Intel i7-8700K - 64GB RAM - NVidia Geforce RTX 3060 - Windows 11 Pro 25H2 -- LR-Classic 15 - Photoshop 27 - Nik Collection 8 - PureRAW 6 - Topaz Photo AI
january01smith
Participant
August 17, 2020

macOS Catalina 10.15.6

dj_paige
Legend
August 17, 2020

Lightroom 4 cannot be installed on Catalina.