Problem with ReportViewer Control in IIS7.5

Hi,

 I have recently migrated a .net 2.0 website (written in vb.net) from IIS 6 to a 64bit windows 2008 server with IIS 7.5. The website uses v10 of the ReportViewer Control

I've tried using the "appcmd migrate config" command to migrate the website from IIS 6 to IIS 7 and I've also manually added the managed handler for the ReportViewer control but no matter what I try I still get the following error when clicking the "View Report" button which causes a postback.

Sys.WebForms.PageRequestManagerServerErrorException: Sys.WebForms.PageRequestManagerServerErrorException: Unable to cast object of type 'Microsoft.Reporting.WebForms.DelegatedRenderingControl' to type 'Microsoft.Reporting.WebForms.ReportViewer'

Does anyone know how to resolve this issue? Please can someone help, its driving me mad.