Error in Web parts after SharePoint platform upgrade

Using MOSS 2007 web part code, i have re build the VS 2010 SharePoint project. After deploying the webpart, i was getting error.

Solution:
I have added below tag in web.config

SafeControl Assembly="MyCustomWebpart, Version=12.0.0.0, Culture=neutral, PublicKeyToken=bdb4a6220fe9433c” Namespace="MyProject.UI.WebParts” TypeName="ListItemReport" Safe="True" SafeAgainstScript="True"