The hotfix update to Prepar3D v4.5 ( is now available. It can be downloaded immediately from the Purchased Downloads section of the website.

Only the Client installer is required for the majority of fixes present in Prepar3D v4.5 Hotfix. The Content, Scenery, and SDK installers are optional. Each fix listed below is categorized per installer. Please note, you must first have Prepar3D v4 installed to utilize any of the standalone installers (Client, Content, and Scenery).

To install the new Client, you must first uninstall your current Prepar3D v4 Client via Programs and Features in Windows Control Panel.

The Prepar3D v4.5 update will require you to reactivate your product, however if you have an internet connection or have not made any major hardware changes between installations this should not be an issue. For more information please view the Prepar3D v4 Download and Installation Directions.

The newly posted Prepar3D v4.5 ( Full Download on the Purchased Downloads page includes the Hotfix.

Please be aware that some third party developers might have to update their add-ons to be compatible with the hotfix. Please contact the third party developers directly for any compatibility questions.

Prepar3D v4.5 Hotfix

Client Fixes and Improvements

      • Fixed performance issues seen on some systems and configurations.
      • Fixed issue where the interpolated wind direction value would be invalid in some cases.
      • Added configuration option to toggle UI hardware acceleration mode (UIHardwareAcceleration).
      • Fixed crash when re-enabling Virtual Reality (VR) while using the Oculus headset.
      • Fixed crash that could occur in some cases after a plugin removed its textures from the system.
      • Varjo eye tracking is now supported.
      • Improved performance when using the Varjo headset.
      • Fixed issue where CreateEffect callbacks would not be issued unless both xyz and pbh offsets were present.
      • CIGI ownship ID now set to 0 for versions prior to CIGI 4.0.
      • Fixed error with empty EntityAffiliation tags being written out in saved scenarios.
      • Fixed issue where sound volume could be incorrect when switching between interior and exterior views.
      • Fixed issue where PBR textures could be black in interior views when first entering a vehicle.
      • Fixed incorrect unit conversions for camera eyepoint altitude P variables.


Content Fixes and Improvements

      • Fixed missing PBR texture in F-16A.
      • Removed light scaling from beacon effects.


Scenery Fixes and Improvements

      • Increased beacon light visibility distance.


SDK Fixes and Improvements

    • Fixed an issue where the PBRMaterial’s effectFile property would not be updated during load.
    • Fixed an issue where 3ds Max exports would throw material mismatch errors when P3DMaterial and PBRMaterial were being used in the same scene.
    • Fixed issue with drawing and loading Annotator vegetation polygons.
    • Fixed several minor errors in documentation.

Thanks again for your support!