This copy of the MacBook Pro Install macOS Monterey application is damaged

Interesting follow up to this, and thanks to @North Hills Guy for mentioning F-secure. I was unable to upgrade to Monterey on my work Mac, a 2019 16" MacBook Pro (Intel Core i9, 16 GB RAM, 1 TB SSD). I received either the 'installer is damaged' error or the 'an error occurred loading the update' error, always about 2 minutes into the install. Trashing and re-downloading the installer did not help. Doing that then booting in Safe Mode and downloading/running the installer did not help. Did not matter if I was on WiFi or Ethernet (via a Stone Pro dock). Booting in Internet Recovery to install the latest OS (Command-Option-R at boot) also failed ('an error occurred loading the update').

My personal Mac is a twin to my work Mac, and had no issues upgrading to Monterey. Nor did my wife's 2020 13" MBP, and I was able to update my kids' MacBook Airs via Internet Recovery (which I did to save having to remove 12 GB worth of data to free up space). Just my work Mac gave this issue.

Although I don't have F-secure, we do use Forticlient for VPN access to the company intranet from offsite. Despite using the VPN Only installer for Forticlient, I did see the occasional requests for permissions that North Hills Guy mentioned, which I had also denied each time.

Long story short, simply quitting the Forticlient app and running the installer did the trick. Honestly, I found this surprising since neither Safe Mode nor even Internet Recovery, neither of which should be affected by a 3rd party app running in the background, enabled me to run the update.

Regardless, I've now got Monterey running successfully on all my Macs.

You could create a bootable installer thumb drive according to this Apple document: How to create a bootable installer for macOS - Apple Support. They work very well.

I had the exact same problem, tried deleting and re-downloading many times. In the end what worked for me was to do the following:

• In the software update dialogue box, click on the More Info in the another update is available section, underneath the install Monterey section:
• 
• In there, I installed the updates to command line for xcode.
• After the update, I restarted my macbook air, then re-downloaded the monterey update. It worked this time...
• Hope this helps!

Just a follow up to this story. When attempting to update to 12.3, I ran into the same problem. In the meantime, I'd been experiencing relatively frequent kernel panics (1-2 times/day) and unexpected app quits. Turns out the problem was hardware, RAM Bank 0 was damaged. So, for those experiencing this issue, it wouldn't hurt to run Apple Diagnostics.

Use Apple Diagnostics to test your Mac

I've had better luck from the Safe Mode because I evidently have some 3rd party software that interferes with the installation so try the following:

#1 - boot into Safe Mode according to Start up your Mac in safe mode - Apple Support.

NOTE: Safe Mode boot can take up to 3-5 minutes as it's doing the following; 

• Verifies your startup disk and attempts to repair directory issues, if needed

• Loads only required kernel extensions (prevents 3rd party kernel/extensions from loading)

• Prevents Startup Items and Login Items from opening automatically

• Disables user-installed fonts 

• Deletes font caches, kernel cache, and other system cache files

#2 - go to the System/Software Update preference pane and begin the download.

#3 - run the installer from the Safe Mode.

It was called F-Secure. I had tried to remove it and number of times but part of the application files were still present. Occasionally it would throw up a message asking for permissions. I always denied the permission bc I didn’t trust the company. I had to “allow” it finally and Monterrey installed. I then got help totally removing F-Secure.

If you have eliminated interference from anti-virus and VPN and similar software, that leaves this:

If you are having problems with the Sierra / High Sierra / Mojave installer running, with an error reading to the effect of "This copy of the Install macOS Mojave.app application is damaged and can’t be used to install macOS", the signing certificate expired. 

source: http://blog.greggant.com/posts/2018/05/07/definitive-mac-pro-upgrade-guide.html#osupgrades

if trying to install but are not yet running 10.11 El Capitan or later, you likely need to UPGRADE to 10.11 as a waypoint before proceeding

If you downloaded some time ago, a fresh download should have a more recent certificate and yield success.

<< quitting the Forticlient app and running the installer did the trick. Honestly, I found this surprising since neither Safe Mode nor even Internet Recovery, neither of which should be affected by a 3rd party app running in the background, enabled me to run the update. >>

I don't get how this should be active in Safe Mode or Internet Recovery either, unless there is something privileged or special about communications software that means it DOES get loaded by Safe Mode and/or Recovery.

¿Does this modify the EFI, or something equivalent?

¿could 'having this active' mean that the Installer was always trying to "phone home" using the VPN?

did you try from Safe mode, which precludes loading of any third-party extensions?

Just to be absolutely certain we are talking about the same thing, the point of Safe Mode is to RUN the Install while still in Safe mode. Inside Safe Mode, no third-party extensions are loaded.

Grant Bennet-Alder wrote:

I don't get how this should be active in Safe Mode or Internet Recovery either, unless there is something privileged or special about communications software that means it DOES get loaded by Safe Mode and/or Recovery.

¿Does this modify the EFI, or something equivalent?

¿could 'having this active' mean that the Installer was always trying to "phone home" using the VPN?

Agree, very odd. I have had prior issues with MacOS upgrades on company-managed Macs when the update was performed offsite (which became an issue with the onset of COVID). In fact, I got locked out of a prior company-provided 15" MBP with the Big Sur update I suspect due to Centrify password management, they had to wipe the machine. However, this work Mac isn't enrolled in any sort of MDM. I had no issues with incremental updates, and this one shipped with Big Sur so this was the first major upgrade.

I'll just remember to quit Forticlient before running the MacOS 13 update (or will it be 14?).

I have the same issue on my MAC 15" Late 2016. I'm currently running Catalina but Monterey say's the installer is damaged. I've trashed it 3 times from applications but say's its damaged on every new download. What is up?

hopemankind wrote:

Hello Guys... I recommend getting CleanmyMac

There is no reason to ever install or run any 3rd party "cleaning", "optimizing", "speed-up", anti-virus, VPN or security apps on your Mac.  This user tip describes what you need to know and do in order to protect your Mac: Effective defenses against malware and other threats - Apple Community.  

There are no known viruses, i.e. self propagating, for Macs.  There are, however, adware and malware which require the user to install although unwittingly most of the time thru sneaky links, etc.   

Anti Virus developers try to group all types as viruses into their ad campaigns of fear.  They do a poor job of the detecting and isolating the adware and malware.  Since there are no viruses these apps use up a lot of system resources searching for what is non-existent and adversely affect system and app performance.

There is one app, Malwarebytes, which was developed by a long time contributor to these forums and a highly respected member of the computer security community, that is desshoigned solely to seek out adware and known malware and remove it.  The free version is more than adequate for most users.  

The above include CleanMyMac. If you search these forums for CMM you'll see many, many posts where CMM was the major factor for the posters problem.

This was one article I found with a simple search. I found it intriguing.

https://www.howtogeek.com/216209/how-to-connect-your-mac-to-any-vpn-and-automatically-reconnect/

.

Apparently, I am showing my ignorance with these questions.

Some searching and reading indicates that Generic VPN support appears to be an integral part of MacOS, but is not 'expressed' as choice on the System preferences > Network menu unless/until you choose to add a VPN.

My guess is that once you make that choice, connecting via some types of VPN does not require any additional software, but is simply 'activated'.

It is conceivable that activating certain types of VPN without the third-party software added is guaranteed to fail.