Windows: Right-click the desktop → Display settings → Display orientation → select orientation (Landscape/Portrait) → Apply
Windows (shortcut): Press Ctrl + Alt + arrow key (Up/Down/Left/Right)
Windows (GPU control panel): Open Intel Graphics Command Center / NVIDIA Control Panel / AMD Radeon Settings → Display → Rotation → choose orientation → Apply
Mac: Apple menu → System Settings (or System Preferences) → Displays → Rotation → select orientation → Close
Mac (if Rotation not available): Use Display settings only if supported by the display/adapter → otherwise use third-party rotation software
Chromebook/ChromeOS: Settings → Device → Displays → Orientation/Rotation (if available) → select orientation
If rotation is stuck: Reboot → update graphics drivers (Windows) → restart display connection (unplug/replug)