CS0104: 'Menu' is an ambiguous reference between 'System.Web.UI.WebControls.Menu' and 'xxx.includes.Menu' Exception occured when i tried to run a 1.1 application on iis 7 iis7 .Net version 2.0  

Solution 

I guess the only solution is to use explicit names 

ambiguous reference between problem solution as mentioned in microsoft.com

Issue 22: Ambiguous references and naming conflicts

The .NET Framework 2.0 adds a host of new namespaces and classes. Several of these are likely to cause clashes with ASP.NET 1.x applications. For example, the new personalization features introduce classes with the names of Profile, Membership, and MembershipUser. The Profile name, in particular, is fairly commonly used by developers who want to keep track of user information. Therefore if you have a Profile class in your application, and you try to use any of the new personalization features, you may encounter compiler warnings about ambiguous class references.
How to fix

Planning ahead for naming conflicts can be rather difficult. You will want to take a quick look through the new ASP.NET classes. If you see any names that might conflict with what you have in your application, you might consider using explicit naming. For example, use System.Web.Security.Membership instead of importing/using System.Web.Security and then using the Membership class.