High Sierra is damaged

[dave2013]

Try to install High Sierra on a Core I5 IvyBridge Intel b75 Motherboard with 16 GB Ram. USB creation went prefect but when I try to install High Sierra it say Installation is corrupt What did I do wrong. Help please!!!

 

[UtterDisbelief]

Try to install High Sierra on a Core I5 IvyBridge Intel b75 Motherboard with 16 GB Ram. USB creation went prefect but when I try to install High Sierra it say Installation is corrupt What did I do wrong. Help please!!!

Hello.

Firstly, please update your hardware profile (someone has already marked this up for you). It's part of the site rules. Thanks.

This error can be caused by a couple of issues:

1) You will need to set the system-date to late 2017 or early 2018 to get around signed certificate problems, depending on the version being used.

2) The other could be caused by how/where you downloaded the High Sierra installer.

 

[wstrohm]

You will need to set the system-date to late 2017 or early 2018 to get around signed certificate problems, depending on the version being used.

If EFI/OC/config.plist/Misc/Security/DmgLoading Value is temporarily changed from "Signed" to "Any" would that also fix the problem?

 

[UtterDisbelief]

If EFI/OC/config.plist/Misc/Security/DmgLoading Value is temporarily changed from "Signed" to "Any" would that also fix the problem?
View attachment 545702

Not sure. You may be on to something.

My thought is that the file is signed but the certificate has expired. Hence the reason to wind back the clock to a point when it was still valid.

 

[c-o-pr]

Try to install High Sierra on a Core I5 IvyBridge Intel b75 Motherboard with 16 GB Ram. USB creation went prefect but when I try to install High Sierra it say Installation is corrupt What did I do wrong. Help please!!!

Web search for "download older versions of macos" and use the apple resources listed.

Installers have a shelf-life of the certificates used to sign them.