restore unsaved changes / files

[mailid4rahul]

I was highlighting text in a Pdf file. once i completed i clicked close window option . it showed want to save changes made to file , by mistake i clicked NO option and my all highlighted text disappeard . I want to restore the file because it took me almost 4-5 hr  highlighting being a 140 page document .Plz help me out . 

Thanx.

[Bernd Alheit]

Highlight the text again.