What were the marburg files in world war ii?

The Marburg files were a collection of documents found at the Marburg Castle in Germany towards then end of the second World War. The documents included various communications from high ranking Nazi officials with the Duke of Windsor, formerly the Prince of Wales, from the English Royal family. He was shown to be a Nazi sympathizer. While this was embarrassing to the British, the British and Americans worked to cover up or limit the exposure of these papers.