WebParts Error after migration from SharePoint2010 to SharePoint 2013

Hello All,

Actually My Question is regarding an error occuring after migration of Content DB and Everything from sharePoint2010 to SharePoint 2013. I am trying to upgrade My Server, But after successful migration of content DB and Site Collections, It is not showing any webPart on the SharePoint 2013 Site. Below is the Error

Error :- 
Web Part Error: A Web Part or Web Form Control on this Page cannot be displayed or imported. The type DemoSharePointUserControl.LyncWebPart.LyncWebPart, DemoSharePointUserControl, Version=1.0.0.0, Culture=neutral, PublicKeyToken=3656b399b713ff03 could not be found or it is not registered as safe. Correlation ID: 2d9c179c-2f58-5051-5762-87aea7d1d9ef

The above error is occuring at the Place in SharePoint 2013 Where our Webpart in SharePoint 2010 Exist.

Please give me some Idea to resolve it.

Thanks