header = Message._get_header(self._msg, header)
         if header == None:
             raise NotmuchError(STATUS.NULL_POINTER)
-        return header.decode('UTF-8')
+        return header.decode('UTF-8', errors='ignore')
 
     def get_filename(self):
         """Returns the file path of the message file
 
         authors = Thread._get_authors(self._thread)
         if authors is None:
             return None
-        return authors.decode('UTF-8')
+        return authors.decode('UTF-8', errors='ignore')
 
     def get_subject(self):
         """Returns the Subject of 'thread'
         subject = Thread._get_subject(self._thread)
         if subject is None:
             return None
-        return subject.decode('UTF-8')
+        return subject.decode('UTF-8', errors='ignore')
 
     def get_newest_date(self):
         """Returns time_t of the newest message date