Hi Theo Jones,
Since other Microsoft Store apps install normally and your default install location is already set to the C: drive, the issue appears to be specific to WinAppRuntime.Main.1.8 and the apps that depend on it, such as Netflix and Prime Video.
As a next step, try repairing the Windows component store and system files:
- Open Command Prompt as Administrator.
- Run:
DISM /Online /Cleanup-Image /RestoreHealth - After it completes, run:
sfc /scannow - Restart your PC and try installing WinAppRuntime.Main.1.8 again before testing Netflix or Prime Video.
If the installation still fails, it would be helpful to know more information as suggested by the Independent Advisor.
Let me know if you need further assistance, feel free to ask me by clicking "Add Comment" or "Add Answer" if you cannot add comment so your response will be visible. Thanks for your effort.
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