Fix an X-Plane 12 demo that will not download, install or launch. Diagnose permissions, drivers, damaged files, add-ons and demo limits.
The X-Plane 12 demo usually stops working because its download is incomplete, the installer lacks permission, security software has quarantined a file, the graphics driver cannot start Vulkan or Metal, or an add-on is crashing the sim. Match the fix to the failure stage: download, installation, launch, or demo operation.
Which part of the X-Plane 12 demo is failing?
The symptom usually identifies whether the fault is in the installer, the simulator or an expected demo restriction.
| Symptom | Likely cause | First action |
|---|---|---|
| Download never starts or repeatedly restarts | Network filtering, security software or insufficient storage | Check free space and retry through an unrestricted connection |
| Installer will not open | Wrong operating-system installer, security block or missing permission | Download the correct installer and approve the official app in the operating system |
| Installation stops on the same file | Damaged download, quarantined file or storage error | Run the installer again and let it scan the existing installation |
| X-Plane opens and immediately closes | Graphics driver, plug-in, preference or damaged application file | Read Log.txt and test without third-party add-ons |
| Black screen or Vulkan/Metal error | Unsupported graphics hardware or driver failure | Install a suitable stable graphics driver and restart the computer |
| Controls work and later stop | The demo session timer has expired | Restart the demo or activate a valid X-Plane 12 licence |
| Scenery is missing outside the demo area | Only the included demonstration region is installed | Test from an airport inside the supplied demo area |
How do I repair the X-Plane 12 demo?
The safest repair sequence starts with the installation and ends with a completely clean copy, preserving the existing folder until the fault is identified.
- Confirm that you have the X-Plane 12 installer for your operating system. Do not use an old X-Plane 11 installer or point an updater at the wrong simulator folder. Our X-Plane 12 demo download and limitations guide explains what should be installed and what the unlicensed version includes.
- Check the destination and available space. The installer needs room for both downloaded data and unpacked files. Use a local folder owned by your user account; avoid a cloud-synchronised folder, network share or restricted system directory while troubleshooting.
- Check security and folder permissions. Allow the official installer through ransomware protection, application control or the macOS security prompt. If a file was quarantined, restore it only after confirming that the installer came from the official source; do not disable all security protection permanently. The detailed installer permissions and failed-repair checklist covers this stage.
- Run the installer against the existing X-Plane folder. Let it scan and replace missing or altered simulator files. If the same file fails every time, investigate security software, disk errors and the connection rather than repeatedly starting the whole download.
- Be patient while files are verified. An installer that shows little visible progress may still be decompressing or writing large files. This is especially easy to mistake for a freeze on macOS; use our Mac-specific diagnosis for slow demo installation before force-quitting it.
- Test X-Plane without additions. Temporarily move only third-party plug-in folders out of
Resources/plugins, remove third-party scenery from the test, and load a stock aircraft at an airport in the demo area. RenameOutput/preferencesso X-Plane can create clean preferences; keep the old folder so controller and graphics settings can be restored later. - Install a separate clean copy if repair fails. Choose a new, empty local folder and add nothing to it. If that copy works, the old installation contains a damaged file, incompatible plug-in or bad preference. Reintroduce items one at a time rather than copying the entire old folder back.
Why do the controls stop working in the demo?
If flight controls work initially and then stop at the same elapsed point in each session, the X-Plane 12 demo timer has expired; this is expected behaviour rather than a joystick fault.
Restarting begins another demo session, while a valid licence removes the time restriction. The demo also supplies only its designated scenery area, so missing terrain elsewhere does not prove that the installation is damaged.
If the joystick is unresponsive from the moment the aircraft loads, open the controller settings, calibrate every axis and check that pitch, roll, yaw and throttle are assigned only once. Duplicate assignments, an incorrect controller profile or a device disconnected during launch can produce the same symptom.
What if a clean X-Plane 12 demo still will not start?
A stock demo that fails from a new folder points to the operating system, graphics stack or hardware rather than an X-Plane add-on.
- Vulkan failure on Windows or Linux: install a stable driver that supports the GPU, restart, and remove overclocking or graphics-injection utilities from the test.
- Metal failure on macOS: confirm that the Mac and operating system support the graphics requirements used by X-Plane 12.
- Out-of-memory message: close other graphics-heavy applications and start with conservative resolution, texture and anti-aliasing settings.
- No window and no new log: security software or the operating system may be blocking the executable before X-Plane starts.
After a failed launch, open Log.txt in the main X-Plane 12 folder before starting the simulator again, because the next launch rewrites it. The last lines can identify a plug-in, scenery package, Vulkan or Metal initialisation failure, missing file or memory error. Our startup-crash workflow for X-Plane 12 explains how to interpret those clues and isolate the failing component.