I have instal addon and fix it in scrapbook.
When i am uninstall the addon and after that i have try to open the scrap book then the foollowing error

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 "DefunctSocialIconsBlockController" 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 C:\wamp\www\concrete5\concrete\models\block.php on line 328