Point # 10 - Disk Cleaners, Optimizers and UnInstaller are not needed. 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. The Built in Security is all that is required.

They are unneeded, cause havoc and interfere with the normal operation of the OS i ncluding the download and installation of Monterey. Point # 9 - AntiVirus Software should be removed as per Developers Instructions. Point # 8 - If downloading Monterey from behind a VPN it may increase Packet Looses and an incomplete or corrupted Installer. Otherwise - ones Privacy and Security touted by the VPN is suspect. Point # 7 - Commercial VPNs should only be used if Mandated by Corporate Head Office for working remotely. Want the maximum bandwidth for the computer being upgraded to Monterey Point # 6 - If using Wifi - move computer as close to the Access Point / Router and disconnect all other devices connected to Wifi. Point # 5 - The upgrade will require a quick, stable and reliable Internet Connection - preferred method is via Ethernet Connection. 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. If upgrading from an earlier release, your Mac needs up to 44GB of available storage. Point # 3 - Empty Space Requirements > If upgrading from macOS Sierra or later, your Mac needs 26GB of available storage to upgrade. Point # 2- > How to upgrade to macOS Monterey Reports indicate the EFI BOOT ROM is Required to Flash the Computer and is a requirement for a Successful Monterey Installation. 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. 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 ? Point # 1 - Does the > Computer Qualify for the Monterey upgrade

The below points should be consider before attempting the upgrade.

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