agcala said:
How to fix the Sharing Tab Missing:

Open Regedit

Go to the following Key

Key: HKEY_CLASSES_ROOT\Directory\shellex\PropertySheetHandlers

Create the following subkey

{f81e9010-6ea4-11ce-a7ff-00aa003ca9f6}

Problem solved
Yep, that's what the .reg file posted above at the link below does. :)

Sharing tab gone missing