I fell into this hole yesterday when I upgraded my wife’s iMac 12,2 (mid 2011) from El Capitan (10.11) to High Sierra (10.13), the final version that the model will run, so that I could install MS Office 2019 for her. The net result is that any program that needs to be updated through the App Store to run under High Sierra, such as Pages, Keynote and Microsoft Remote Desktop, fails to run and quits with a “code signature invalid” error.
The contributors to the above thread have determined that the fault lies at Apple’s end, in the software that validates new software installations. So far Apple has not acknowledged the fault. If it doesn’t resolve it, many people who can’t upgrade beyond High Sierra are going to have to downgrade (if possible) or buy new Macs.
Is this by design to strongly encourage all us to get in step with the program? Has Apple decided to abandon support for High Sierra? I sure hope not as I have family members who love it and do not want to upgrade. Frankly, I ask myself several times a day why did I update to Catalina and abandon High Sierra and Mojave? A couple of my most favorite research apps refused to update to the new Catalina or Mojave now I don’t have them and stepping back would be an absolute nightmare.
On page 8 of that discussion, FrancoisQC this morning seems to have what seems to be a fix that when done for one application seems to fix all programs:
From a clean reboot, run in terminal “spctl --assess -v /Applications/YourApp.app”
From a Finder window, under Applications, right-click (Ctrl-Click) on your app, and select “Signer Info”
Enjoy your app
I have not tried it on the machine I experienced the problem on. Hopefully this works for everyone.
I’m following that thread. So far there are two possible terminal workarounds. One involves the command spctl, the other codesign. No idea which one I should attempt first! It’s an interesting thread for sure.
Thanks for updating us. I tried the suggestion solution by FrançoisQC quoted above and it worked! This should keep folk in business until Apple resolves the error.
The previous solution did not stick across reboots for some people. There’s a new one by the same poster that appears to work better:
Hope this helps everyone:
Open a terminal
run the following command
sudo rm -f /Library/Keychains/crls/valid.sqlite3
I haven’t tested, but I think a reboot is not even necessary. And this does survive a reboot.
It looks like this file may be used by “trustd”. So worse case scenario, this will rebuid trustd’s cache, so that should not affect the security of your system.
There’s a new solution that appears to work by rebuilding a cache:
Hope this helps everyone:
Open a terminal
run the following command
sudo rm -f /Library/Keychains/crls/valid.sqlite3
I haven’t tested, but I think a reboot is not even necessary. And this does survive a reboot.
It looks like this file may be used by “trustd”. So worse case scenario, this will rebuid trustd’s cache, so that should not affect the security of your system.
I’m not sure that’s a helpful strategy for someone who already owns a license or subscription for Microsoft Office, especially if they have the version that offers several full sublicenses to “family” members. I’m not at all opposed to open solutions and alternatives, but the install hassles that may be bypassed will simply be supplanted with interoperability hassles or holes in functionality.
The OP’s needs may not run into that, but they have a license and they’d like to use it without moving away from High Sierra. (I did that on my laptop this summer, to Mojave, and I’m sorry I did.)
This is regarding High Sierra installs which were downloaded after November 12, 2020, and App Store apps not launching due to a codesigning error (along with some other App Store weirdness). There’s some progress in figuring out what’s causing this, though thanks to Apple’s typical opacity it’s all speculative, as well as some workarounds. Not quite sure we have a permanent fix but the tweak’s fairly simple and may only have to be repeated every few days, while we wait for Apple to fix things on their end.
It involves a certificate revocation list database, a timeline of versioning for updates of that database, and High Sierra’s practice of not using OCSP as a fallback for a sketchy certificate.
In addition to Colleen’s clarifying comments, I did not mean to imply that there is a problem with Office installing on either of those operating systems. I’m using Office 365, which works quite well on both. Beyond that I don’t want to highjack this thread beyond my original remark which was a response to the suggestion of abandoning MS Office for Open Office in order to avoid confronting an OS upgrade.
