please delete this

Mathijs, I cannot reproduce your scenario using TC 11.31 on Windows 7 - Delete deletes the project folder for me. AFAIK, Delete can handle external files (outside the project folder), read-only files, etc. So unless the leftover files/folders are locked by another application, or there are non-TestComplete files in the project folder, I'm not sure why the files would be left behind. I would recommend asking our support team about this.