Hi Philip,
· Which version of Microsoft Flight Simulator X are you using?
According to Windows 8.1 compatibility center. Microsoft Flight Simulator X version 10 is compatable with Windows 8.1. Refer this link. You may face this issue if graphic card drivers is not updated.
I would suggest you to uninstall and reinstall the Graphic card drivers and check.
Follow these steps to update the drivers for Graphic card. You may also check for drivers using Windows Update. If issue still persist download drivers from computer manufacture.
You must be logged on as an administrator to perform these steps.
- Open Device Manager by pressing Windows key + X, clicking Control Panel, clicking System and Maintenance, and then clicking Device Manager. If you are prompted for an administrator password or confirmation, type the password or provide confirmation.
- In Device Manager, locate the device you want to update, and then double-click the device name.
- Click the Driver tab, and then click Update Driver and follow the instructions.
If Windows Update can't find a driver for your device, check the device manufacturer's website. Refer these links and check if it helps:
You may also contact Microsoft Flight Simulator support and check:
http://www.microsoft.com/products/games/fsinsider/tips/pages/default.aspx
Hope this helps. If you need further assistance with Windows, let us know and will be glad to help.