Help! System not recognizing unity package.

I don't how did this happened, all the unity package files just suddenly become unrecognizable (white file icon) every time I need to import a package I have to go to import menu to import it instead of just click on it. I tried to use "open with" to fix it but every time I tell unity to open this it just open up another unity window.

 

I usually just drag .unitypackage files into my Project window. Does that work? You have to have the search bar empty before it will work, usually.

 

Thanks for replies, I tried to drag them in the window, and unity will just import the package itself into the folder because it doesn't know what type of file is it. But for some reason it works again yesterday, even though I still couldn't click on the file and import it into the scene but the drag and drop method somehow fixed itself.