I cannot edit my document in LibreOffice 3.5 because some part of it has mysteriously been protected (and normal methods for disabling protection, e.g. going to Formatting and disabling protection, don’t work). I cannot edit the portion of text marked read-only (I am the only person with access to this document: how am I not allowed to work on my own stuff?). No password prompt is given (and I don’t have a password anyway, since I have no interest in protecting my work from myself or anybody else).
Menu/Tools/Protection.
Menu/File/Properties/Security - Open file read only.
Is the file in edit mode?
Click the edit Icon