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Updated February 6, 2026 by Sarah Hutchinson, Director of Digital Content, ConcreteNetwork.com
Because you are using a specific 2021 build, you might encounter these issues:
1. “This copy of the Install macOS Big Sur application is damaged”
2. “The operation couldn’t be completed. (PID = 0)” in VMware
3. Missing firmware for M1 Macs
Apple officially distributes macOS through the App Store as a .app bundle. However, advanced users, IT administrators, and virtual machine enthusiasts often require a bootable ISO image for:
The 2021 ISO releases (typically build 20G413 for 11.6.2 or similar) represent the most stable and polished iteration of Big Sur before Apple shifted focus to macOS Monterey in late 2021.
Q: Is there a difference between the 2020 ISO and the 2021 ISO?
A: Yes. The 2021 version (11.3+) includes support for Radeon RX 6000 series GPUs, which is vital for Hackintosh users. The 2020 version (11.0.1) has a critical memory leak in WindowServer. macos big sur iso 2021
Q: Can I use this 2021 ISO to dual boot on a Windows PC?
A: No. Dual booting macOS on standard PC hardware (Hackintosh) requires OpenCore, not a raw ISO. You would extract the .app from the ISO and use OpenCore’s installer.
Q: The file I downloaded says “BigSur2021.iso” but it’s only 500MB. A: You have downloaded a fake. A real macOS Big Sur ISO is 12GB to 14GB. Delete it immediately.
Q: I have a 2021 MacBook Pro (Intel). Can I use this ISO to do a clean install?
A: Yes, but it’s inefficient. Use Internet Recovery (Option+Command+R) instead. The ISO is best for virtual machines or external USB creation. Because you are using a specific 2021 build,
The 2021 ISO is specifically required for VMware because newer macOS versions (Ventura+) require hardware NVRAM fixes that break on older VMware versions.
Configuration for VMware Workstation Pro 17:
BigSur2021.iso.F2 -> Virtualize CPU -> Enable “PMU Virtualization”.The 2021 ISO will install in roughly 15 minutes. Do not accept updates to Monterey during setup. Before we proceed
Before we proceed, a strict warning: Avoid untrusted “pre-made” macOS Big Sur ISO files from torrent sites or random blogs.
The Golden Rule: Never trust a pre-made ISO. Always create your own using the official Apple installer.
Because you are using a specific 2021 build, you might encounter these issues:
1. “This copy of the Install macOS Big Sur application is damaged”
2. “The operation couldn’t be completed. (PID = 0)” in VMware
3. Missing firmware for M1 Macs
Apple officially distributes macOS through the App Store as a .app bundle. However, advanced users, IT administrators, and virtual machine enthusiasts often require a bootable ISO image for:
The 2021 ISO releases (typically build 20G413 for 11.6.2 or similar) represent the most stable and polished iteration of Big Sur before Apple shifted focus to macOS Monterey in late 2021.
Q: Is there a difference between the 2020 ISO and the 2021 ISO?
A: Yes. The 2021 version (11.3+) includes support for Radeon RX 6000 series GPUs, which is vital for Hackintosh users. The 2020 version (11.0.1) has a critical memory leak in WindowServer.
Q: Can I use this 2021 ISO to dual boot on a Windows PC?
A: No. Dual booting macOS on standard PC hardware (Hackintosh) requires OpenCore, not a raw ISO. You would extract the .app from the ISO and use OpenCore’s installer.
Q: The file I downloaded says “BigSur2021.iso” but it’s only 500MB. A: You have downloaded a fake. A real macOS Big Sur ISO is 12GB to 14GB. Delete it immediately.
Q: I have a 2021 MacBook Pro (Intel). Can I use this ISO to do a clean install?
A: Yes, but it’s inefficient. Use Internet Recovery (Option+Command+R) instead. The ISO is best for virtual machines or external USB creation.
The 2021 ISO is specifically required for VMware because newer macOS versions (Ventura+) require hardware NVRAM fixes that break on older VMware versions.
Configuration for VMware Workstation Pro 17:
BigSur2021.iso.F2 -> Virtualize CPU -> Enable “PMU Virtualization”.The 2021 ISO will install in roughly 15 minutes. Do not accept updates to Monterey during setup.
Before we proceed, a strict warning: Avoid untrusted “pre-made” macOS Big Sur ISO files from torrent sites or random blogs.
The Golden Rule: Never trust a pre-made ISO. Always create your own using the official Apple installer.