In windows 7 there is a shared folder between several computers. All files are visible from another computer, open, etc. The problem occurs when using the scanner through the canon mf scan utility in it creates a new pdf. 
It is created protected and has to be unlocked manually. If you create it in another folder, then everything is fine. In the settings cannon mf found such settings. The problem arose (as they say) after the acrobat reader was put, then it was removed, before that everything was fine.
