Settings reference
Open Settings from the application's settings control. Select a page, make the required changes, and confirm the dialog to apply them. Cancel discards the dialog's pending changes. A separate confirmation or restart prompt explains changes that need additional action.
Automatic optimization and boot-time optimization are configured on their own main views. On Boot-Time Optimization, mode and drive changes apply immediately, including to an already scheduled run. Use its start or schedule buttons to request a one-time run.
General
Choose the available language and appearance preferences. A language change affects interface text; an appearance change affects light, dark, or high-contrast presentation. Follow an application restart prompt if shown.
Performance
Set Defrag's CPU and disk load limits, overall-load start guards, blocked processes, and stopping on battery. These are global defaults; jobs can have their own settings. See Activity Monitor.
Optimization
| Setting | Purpose |
|---|---|
| Check drives before defragmentation and abort upon error | Check for file-system errors before moving files. |
| Optimize multiple physical drives in parallel | Allow simultaneous work on separate physical devices. |
| Use system recommendations for file-system layout | Use available Windows layout guidance. |
| ROI factor | Skip low-benefit rewriting with SOLID and SOLID/Complete. |
| Do not report ROI-exempt fragmentation | Align reported fragmentation with the ROI policy. |
| Include removable/external drives | Include these drive categories in eligible operations. |
| Prevent defragmentation of solid state drives | Prevent SSD defragmentation under these options. |
| Skip drives containing shadow copies of other systems | Avoid those drives. |
| Disable automatic optimization | Disable background optimization in the agent options. |
| File drives into zones | Enable zone filing across volumes; not recommended for SSDs. |
| Enable remote administration from same network | Permit management from other PCs on the same subnet. |
Only enable remote administration for an intended administration setup. It changes access to the agent; it does not turn a network share into a locally optimizable disk or add a remote-management console to this guide.
New jobs inherit global defaults when created. Review existing jobs separately after changing these settings.
Files
Manage excluded paths, forced-inclusion paths, and the large-file limit. Matching inclusions take precedence over exclusions. See File rules.
ClusterView
Change block size, DPI adjustment, shading, the 3D effect, and selection emphasis. These affect visualization only.
Drive detection
Correct the media type when Windows reports it incorrectly. Confirming a changed type may require the agent to restart, so finish active work first. See Drive detection.
Reports
Enable report creation, set a retention count between 1 and 999, choose Windows event-log detail, and control the summary and tray options. See Reports and logs.
Expert mode
Choose whether O&O Defrag should start in the classic interface. See Interface.
Logging and advanced diagnostics
Enable application logging on the logging page when investigating a problem. The advanced page, available when opening Settings with Shift held, includes engine logging and resetting user settings.
Use reset only when you intend to restore preferences and have the necessary license information. It can require an application restart and re-entry of licensing data. For ordinary troubleshooting, start with logs rather than a reset.
Unavailable settings
Agent-backed pages stay unavailable until a valid current configuration is received. Wait for connection or update a mismatched service. Do not interpret a disabled control as the current value of the setting.