shares sent to friends by e-mail or via facebook could not be viewed since the last updates. Message appears that user don't have sufficient rights to see this entry...
When you display an activity, there is a small padlock icon, located just to the left of the word "share". The padlock has to show as "open" before anyone else but you can view your activity.
Clicking the padlock will toggle it between public and private.
Note that on the Settings page, you can set the default privacy setting for your new uploads. Previously loaded activities remain unchanged when you change your default in the Settings page. You would still have to change those individually.
