IMac gets stuck trying to open software updates

January 21  2022 Version # 3

The below points should be consider before attempting the upgrade.

Point # 1 - Does the >>  Computer Qualify for the Monterey upgrade 

Point # 1A - There are reports appearing on the ASC Forums regarding failed installation of Monterey on older Qualifying Apple Computers. In most cases this is related to having a NON Apple Original internal drive ?  

The EFI Boot ROM included in Monterey is verifying for Original Apple Drive and if not found , may Balk or fail to upgrade to Monterey. 

Reports indicate the EFI BOOT ROM is Required to Flash the Computer and is a  requirement for a Successful Monterey Installation.

Point # 2- >> How to upgrade to macOS Monterey

Point # 3 - Empty Space Requirements  >> If upgrading from macOS Sierra or later, your Mac needs 26GB of available storage to upgrade. If upgrading from an earlier release, your Mac needs up to 44GB of available storage. 

Point # 4 - Empty Space afterwards - it is suggested to keep at least 15% of the Drive Total Capacity as Empty Space for good operations of the computer and for additional updates to Monterey to download, expand and install.

Point # 5 - The upgrade will require a quick, stable and reliable Internet Connection - preferred method is via Ethernet Connection. 

Point # 6 - If using Wifi - move computer as close to the Access Point / Router and disconnect all other devices connected to Wifi. Want the maximum bandwidth for the computer being upgraded to Monterey

Point # 7 - Commercial VPNs should only be used if Mandated by Corporate Head Office for working remotely. Otherwise - ones Privacy and Security touted by the VPN is suspect. 

Point # 8 - If downloading Monterey from behind a VPN it may increase Packet Looses and an incomplete or corrupted Installer.

Point # 9 - AntiVirus Software should be removed as per Developers Instructions. They are unneeded, cause havoc and interfere with the normal operation of the OS including the download and installation of Monterey. 

The Built in Security  is all that is required. 

There are no known Windows-like Viruses in the wild that self replicate and affect macOS because of the underling UNIX  Foundation and Permission Limitation. 

Point # 10 - Disk Cleaners, Optimizers and UnInstaller are not needed. They will often times attempt to Modify, Alter, Remove or Delete elements of the Operating System requiring a Re-Installation.

Point # 11 - Do you have a Rescue Plan In-Place. This comprises having 3 Backups using 2 methods and 1 Off Site incase of Theft, Loss or Natural Disasters. A Time Machine Backup  is very useful and can be used to Revert to Previous Working macOS. 

Point # 12 - For addition purposes - two Tested Bootable Clones each to separate external drives. This is insurance incase the upgrades goes sideways. At least one Tested Clone and / or Time Machine Backup should be Off - Site

Point # 13 - Are the installed Applications / Extensions compatible with Monterey. Check with the Developer for compatible Apps / extensions. Do they offer updates or upgrades. Same goes for Third Party Drivers for Printer, Scanners etc.

The deletion of the Flash Player icon is not causing the issue. Flash is outdated and therefore not running anymore on your new OS.

To fix the issue with the software update try the following:

• Get the latest update for your OS by downloading it manually from here: https://support.apple.com/en_US/downloads/macos
• After the installation is complete, delete the following two files. (Honestly, I copied them to a temporary folder beforehand just in case, so I could restore them if I was in doubt):

~/Library/Preferences/com.apple.SoftwareUpdate.pIist.plist
~/Library/Preferences/com.apple.preferences.softwareupdate.plist

• Now restart your Mac and the problem should be gone.

By the way, I am using Catalina, but the steps should work in any other version of macOS that is still receiving updates.

Apple makes three kinds of software patches for the operating system.

Updates. These are found in Apple menu -> System Preferences -> Software Update, or Apple menu -> About This Mac -> Software Update. They are released intermittently throughout the year. Prior to Big Sur, Apple also included them on https://support.apple.com/downloads and were released there as delta and combo versions. The delta jump one step, and the combo brings any earlier updates up to date to the current.

Security updates - Like updates themselves, typically patch the last update release, and again prior to Big Sur were also released on https://support.apple.com/downloads and always on Apple menu -> About This Mac -> Software Update and Apple menu -> System Preferences -> Software Update

Upgrades - Annual releases only available on the App Store and part of system restore on a Mac.

The App Store started releasing upgrades in Apple menu -> App Store with the release of Lion, 10.7.

Since that time, they have released annual upgrades:

10.7 Lion, 10.8 Mountain Lion, 10.9 Mavericks, 10.10 Yosemite, 10.11 El Capitan, 10.12 Sierra, 10.13 High Sierra, 10.14 Mojave

10.15 Catalina, 11 Big Sur, 12 Monterey

Updates typically had an additional period after the initial name. Monterey is currently at 12.1, and there were 6.2 updates for Big Sur, 7 updates for Catalina, 6 updates for Mojave, High Sierra, Sierra, El Capitan, 5 for Yosemite, Mavericks, Mountain Lion, and Lion.

The main thing to remember, backups are always recommended, keeping sufficient space of at least 15% free plus the recommended minimums, and verifying compatibility of upgrades exist before performing them.

So when you go to Apple menu -> About This Mac, what does it say you have now?

I fixed it by resetting the Software Update preferences. Open a terminal and type:

sudo rm /Library/Preferences/com.apple.SoftwareUpdate.plist

Fill in your password (it will not show that you're typing) and press enter. Then reboot your Mac.

Software Update, as I say will not deal with Upgrades.

Monterey is an Upgrade.

App Store is the only place you'll find that until it becomes an "Old Version".