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Why won’t my Mac boot after the macOS 26.3 update with Check Point Harmony?
Critical Warning: Halt Your macOS 26.3 Update
If you use Check Point Harmony Endpoint protection, do not update to macOS 26.3 Tahoe immediately. Users report severe boot failures following the update released on February 11, 2026. The conflict triggers a boot loop that forces the system into recovery mode, rendering the device unusable for standard operations.
The Technical Conflict
The core issue involves an incompatibility between the macOS 26.3 kernel or boot process and the Check Point Harmony Endpoint driver.
- Symptoms: After the update completes and the device restarts, it fails to load the operating system.
- Outcome: The Mac enters Recovery Mode automatically and may prompt you to reinstall the OS.
- Root Cause: Preliminary reports suggest the issue stems from the Endpoint Security framework interaction in versions E88.x and E89.x of the Harmony client
Immediate Action Plan for Admins
System administrators must block the macOS 26.3 update for all managed devices running Check Point Harmony.
- Prevention: Enforce a delay on OS updates via your MDM (Mobile Device Management) solution immediately.
- Remediation: If a device is already affected, uninstalling Check Point Harmony via Recovery Mode (if terminal access allows) or restoring from a backup is the only current public recourse.
- Vendor Status: Check Point has confirmed the critical failure. They advise customers to pause updates while their engineering team investigates the root cause.
Vendor Response and Workarounds
Check Point has acknowledged the crash in a support document titled “Upgrade to macOS 26.3 causes computer to enter recovery and not boot”.
- Official Fix: There is no publicly available patch as of February 18, 2026.
- Restricted Workaround: A specific workaround exists but is gated behind the Check Point User Center. You must log in to your enterprise account or contact support directly to access these instructions.
- Next Steps: Monitor the official Check Point support page for a hotfix before attempting any further OS upgrades.
Context: macOS 26.3 and Harmony
Check Point Harmony is an advanced endpoint protection suite that includes VPN and threat emulation capabilities. These deep system integrations often require precise compatibility with macOS kernel extensions. macOS 26.3 Tahoe, released to address high-severity vulnerabilities (CVSS 8.8), introduced changes that evidently broke this integration. While the OS update fixes critical security gaps, the operational risk of a bricked fleet currently outweighs the patch benefits for Harmony users.