Class ' Webform' and class 'Webform' in 'c:\......' conflict in namespace 'XName"

I created a new project and then took an existing projects and put the contents in the new projects changing the name, table calls, etc. because the new projects is very simular as the copy one. But when I rebuild the new project I receive the error message: Class ' Webform' and class 'Webform' in 'c:\......' conflict in namespace 'XName'
This is how I setup my Webform:
 
Public Class WebForm1     Inherits System.Web.UI.Page
#Region " Web Form Designer Generated Code "
    'This call is required by the Web Form Designer.     <System.Diagnostics.DebuggerStepThrough()> Private Sub InitializeComponent()
    End Sub
    'NOTE: The following placeholder declaration is required by the Web Form Designer.     'Do not delete or move it.     Private designerPlaceholderDeclaration As System.Object
...