Microsoft SharePoint Server State Service could not retrieve data for a specified key. This can occur if the database was ...

Microsoft SharePoint Server State Service could not retrieve data for a specified key. This can occur if the database was removed from a service application's group of databases, if a database was deleted from the farm, or if the web application's service connection to a State Service Application Proxy was removed.  (Request Context - URL: %1, State Database Identity: %2)