hi1 user found helpful
Fatal error: Block::getInstance() [<a href='block.getinstance'>block.getinstance</a>]: The script tried to execute a method or access a property of an incomplete object. Please ensure that the class definition "SocialSharePrivacyBlockController" of the object you are trying to operate on was loaded _before_ unserialize() gets called or provide a __autoload() function to load the class definition in /home/etrend5/public_html/c5/concrete/models/block.php on line 329
please help ASAP none of them is working.
What you could do is re-add that block from the market place so that things load again, then delete the instance off of the page, and then re-remove it if you don't want it anymore.
Hopefully that helps out