Answer by Liyun Zhang - MSFT for Namespace not recognised / found in Maui project

Did you code the project by your self or just copy the official sample on the github?

I can reproduce your problem by using the special class in the Platforms\Windows folder. But you can run the project successfully if you ignore it.

And if you want to make the error disappear. You can use theconditional compilation:

#if WINDOWSusing VideoDemos.Platforms.Windows;#endif

In addition, you can double check if there is anything different between your code and official sample.