Newbie question: Why are some folders greyed out?

I highlighted and copied some folders containing music from my local HDD and pasted them onto my external HDD.

The folders are greyed out and I am unable to open them.

I got the window with the blue barber pole showing that it was preparing to copy. Clicked to Safari and surfed a little. I clicked back to Finder, the message window was gone and I assumed that the folders were pasted. However, they are still greyed out.

Any comments, advice, learning tips?

Is the process still copying the files over?

That's the problem. I don't know how to determine whether the process is over not. I assume that it is since the barber pole message window is gone, however the folders are still greyed out. So, it seems as if the process is not done, but it has been about 30 minutes.