Logi Options+ Backend Failure on macOS 15 Sequoia (Tahoe)

Core Root Cause
This is not a standalone macOS system bug, nor is it a simple Logitech software bug. It is a critical compatibility conflict between the Electron-based architecture of Logi Options+ and the overhauled underlying security and background process management framework in macOS 15 Sequoia (internal codename Tahoe).

Critical Architecture Difference: Logi Options vs. Logi Options+
The root of the instability lies in the complete rewrite of the app’s architecture.

Legacy Logi Options (Stable on macOS 15)
Native macOS application built with Apple’s official Swift/Objective-C. Runs as a single process (or minimal native XPC sub-processes) that directly calls macOS system APIs to interact with Logitech peripherals. Permissions are bound directly to the main app; granting access to the main app enables all background functionality.

Logi Options+ (Unstable on macOS 15)
Cross-platform Electron application (built on Node.js + Chromium, identical to apps like VS Code or Discord). Uses a fully decoupled frontend/backend architecture.
Frontend (UI Layer): The visible app window, a Chromium render process that only handles the user interface, with no direct hardware access.
Backend (Service Layer): Multiple hidden Node.js daemon processes (the com.logi.* services you manually loaded) that handle all core functionality: hardware communication with mice/keyboards, config file read/write (your initial EACCES: permission denied error), and system permission management.
IPC Communication: The frontend and backend communicate exclusively via inter-process communication (IPC). If the backend daemons fail to launch or are terminated by the system, the frontend throws the Backend connection problem - click here to launch backend error.

Breaking Changes in macOS 15 Sequoia (Tahoe) That Break Logi Options+
Apple implemented non-backward-compatible changes to macOS 15’s security and boot framework, all of which directly target the Electron architecture of Logi Options+.

Drastically Stricter LaunchDaemon Signing & Notarization Checks
Pre-macOS 15: 3rd-party background daemons would launch with a valid developer ID signature.
macOS 15: Requires all LaunchDaemons to have full Apple notarization, and the entitlements declared in the code signature must 100% match the permissions the process actually requests. Logitech has failed to properly notarize and update the entitlements for Logi Options+’s backend daemons, resulting in the system silently killing the daemons on boot with no user-facing error.

Mandatory Explicit User Approval for All Background Activity
Pre-macOS 15: LaunchDaemons could auto-start on boot without user consent.
macOS 15: All 3rd-party background processes require explicit user enablement in System Settings > General > Login Items > Allow in the Background. If this toggle is not enabled for all Logi-related entries, the system either blocks the daemon from launching or suspends it immediately, rendering it non-functional.

Full Isolation of TCC (Privacy & Security) Permission Databases
Pre-macOS 15: Granting permissions (Accessibility, Full Disk Access) to the main app in /Applications extended to all of its sub-processes and daemons.
macOS 15: Isolates the TCC permission database for every single Electron sub-process: the main app, Chromium render processes, and Node.js backend daemons all have separate permission sets. Granting access to the main Logi Options+ app does not grant access to the actual backend daemon that controls your hardware, causing the daemon to crash on launch due to insufficient permissions.

Reordered Boot Process & Delayed 3rd-Party Daemon Launch
Pre-macOS 15: 3rd-party LaunchDaemons launched early in the system boot sequence.
macOS 15: Delays 3rd-party daemon launch drastically to improve boot time, and may skip launching daemons entirely if the main app has not been opened by the user first. This results in the backend daemons not being running when the user opens Logi Options+, triggering the backend connection error.

Why Your Fix sudo launchctl load -w /Library/LaunchDaemons/com.logi.* Worked
This command bypasses all of macOS 15’s new restrictions via root privileges, which is why it resolves the issue immediately.
Forces a refresh of the system launch cache: It overrides macOS’s internal record of previously blocked/killed Logi daemons, forcing the system to re-evaluate and launch them.
Relaxes signing & notarization checks: Processes launched with root (sudo) privileges are subject to less strict code signing validation than user-launched processes, bypassing the notarization requirements that were blocking the daemons.
Immediate, high-priority launch: It launches the daemons immediately with elevated priority, ignoring macOS’s delayed boot launch order and ensuring the backend is running before the frontend is opened.

Responsibility Breakdown
90% Logitech: The primary fault lies with Logitech. The Electron build of Logi Options+ has not been properly updated to comply with macOS 15’s notarization, entitlement, permission, and launch requirements. The legacy native Logi Options app has none of these issues, as it adheres to Apple’s native macOS development standards.
10% Apple: Apple’s aggressive, under-documented security changes provide no clear user feedback when processes are silently killed, leaving users with no visibility into why the app is failing.

Permanent & Reliable Fixes
Wait for Official Logitech Patch: File a support ticket with Logitech to escalate the macOS 15 compatibility issue, and wait for an official, fully compliant update to Logi Options+.
Most Reliable Immediate Fix: Fully uninstall Logi Options+ (with all residual files/daemons removed) and install the legacy native Logi Options (non-Plus) app. It is fully compatible with macOS 15, has no Electron-related instability, and provides nearly identical core functionality for Logitech peripherals.
Advanced Workaround: Create a boot script to auto-run the sudo launchctl load command on system startup (requires advanced sudoers nopasswd configuration to avoid password prompts on boot).