PDF dissappear after making notes and saving

Now this has same thing has happened several times.

  1. I import a text sent to me as a PDF.
  2. In order to be able to make some notes while reading I open it from DT pro to Preview.
  3. Read and comment
  4. Save.
  5. Work with other things. A couple of days pass (this specific time 7 days).
    6 Try to open the PDF in DTpro again. But it just an Icon nothing else.
    a small image, a miniature of the first page…

Have anyone else experienced this?


What’s the path of the PDF document and is there a PDF document?