Unlocking 'resistant' files

I have tried in vain, all the methods googling suggested, for removing the lock image from the icons for certain batch files in Win7-Ultimate-32bit. There are very few of these where the lock persists, despite changing 'forceguest' in the
registry. For these 'locked' files, their context menu lacks the 'share with' option. Is there a way of 'unlocking' these few 'select' files ?