windows phone 8 - How To add file to <Assets> folder on WP8 or WP8.1 -

I want to add that file to the folder, after that I added that file, I add that file to the Assets folder In the attempted solution, but unsuccessful, it shows an error box:

  The desired name of "D: \ ....." is invalid  

< P> However I can not add it to the resolved folder.

Do I have to add some stuff to * .xaml first? What is the correct way to add a file to that WP pack it in the last app?

Thank you.

In Solution Explorer, right-click on the Asset folder and select Add.Existing item ... menu option Please. Find the file you want to add and it will be copied to the Assets folder in the solution.

To ensure that it is packed with the app, select the properties of the item in the Solution Explorer and make sure the build action is "content". This will be the default for the common C beginners type (.png, .jpg, etc.) but you have to set it explicitly for other content types.

If you do not want to add a blinded file, you can edit it directly, create a project file or a mapping file and package itself to make the file itself with the Visual Studio instead of the package with the MixPack .