Roll a ball tutorial error-2 Moving the Player

while I m doing tutorial Roll a ball- Moving the Player . the error occur-
Could not load project ‘Roll a ball.csproj’ with unknown item type ‘{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}’

whenever I try to open C# Script error happen like above.

can you solve this problem?

sorry for my english . Im not a native english speaker.

good luck.

I can’t move the ball, too.