Issue - An error message is displayed showing the text  ‘E_Fail: An undetermined error occurred (-2147467259) and the game crashes.
This error appears on the PC version downloaded from - www.strongholdkingdoms.com

Cause - The problem has been caused by Intel removing native support for DirectX 9 from some of their discrete and integrated GPUs (Xe graphics, Intel Arc).
You can read this issue in more detail here (non Firefly Studios page)  

Workaround - 

You may try going to Device Manager, then Display Adapters, then right clicking on Intel Graphics and disabling.

If your computer/laptop has another graphic card, such as a Nvidia or AMD Card

To run Stronghold Kingdoms on your dedicated graphics card please follow these steps (use at your own discretion):

Step One: Use the Windows key + I to open up Settings.

Step Two: Click on “System” then "Display" then “Graphics settings” (Windows 10) or "Graphics "Windows 11).

Step Three: Click "Browse" and browse to the folder containing the "Stronghold Kingdoms.exe" application file. Select the "Stronghold Kingdoms.exe" file and click "Add".

NOTE: Default installation folder is C:\Program Files (x86)\Firefly Studios\Stronghold Kingdoms

Step Four: Once added, find Stronghold Kingdoms in the list below and click “Options”

Step Five:  Select “High Performance” to use your dedicated graphic card (Nvidia, AMD, etc) when playing Stronghold Kingdoms.  Click "Save".

If your computer/laptop does not have another dedicated graphics card
We are currently investigating a long-term solution to this issue in the meantime download our alternative version of Stronghold Kingdoms, built in Unity, available in the Microsoft Store. To find this - Type Store into the Window Search bar. Search for ‘Stronghold Kingdoms’ and download. Click on Play Stronghold Kingdoms via the Store page. Login using your normal Stronghold login details.