upgrade to .net 4.5 Iframe issue

http://stackoverflow.com/questions/17809446/iframe-parser-error-after-upgrading-to-net-4-5

You need to add below tag.

<asp:HtmlIframe>

In the designer change the control type to

System.Web.UI.HtmlControls.HtmlIframe

Add the below line in ur Webconfig

<controls>
 <add tagPrefix="asp" namespace="System.Web.UI.HtmlControls" assembly="System.Web"/>
</controls>

This should fix..