====== Remove editing restrictions in Word 2010 with 7zip ======

  - Make a copy of the original document and rename it to have the .zip extension.
  - Extract .zip file and in the contents find word\settings.xml
  - Edit settings.xml to remove the XML element beginning with w:documentprotection. Remove everything including < and >
  - Copy the word directory to the same location as your document.zip file.
  - Rename your file to word.zip
  - Right click word directory and choose 7zip -> Add to "word.zip"
  - Rename word.zip to yourformname.docx
  - Do a little dance and be happy that this episode of your life is now over.

Source: http://itintheory.blogspot.co.at/2012/06/remove-editing-restrictions-in-word.html