Cannot convert type ‘Microsoft.SharePoint.WebControls.DelegateControl’ to ‘System.Web.UI.IAttributeAccessor’
This error mostly happens when you try to edit the master page.
To fix it
- open the master page in notepad
- You’ll see a big chunk of html code that is commented out.
- Mostly this will be at the end of the page after </html> tag.
- Delete that chunk of data. The master page will work properly again.
Now check your page in browser which is error free.