Howto clean Photo Folder I opened Photo. I deleted all the pictures. Then I emptied the "Deleted images".

My Photo app is apparently empty.

I open finder, the photo library package is around 7GB an subfolders are full of old images and other unknown files.

I wish to clean all, to gain a fresh empty Library.

If I delete the .photoslibrary folder, the app shows an error message. 

Can someone tell me the right procedure, please?
You can create a new library by opening iPhoto whilst holding ⌥ alt/option. This creates a fresh iPhoto library which you can import media into.