Client applications that use a Web service may not work as expected after you upgrade to ASP.NET 2.0

Consider the following scenario:

• You host an .asmx Web page on a computer where the Microsoft .NET Framework 1.1 is installed. The Web service page contains an Enum class.
• Client applications that use the Web service work as expected to generate a Web service proxy file for the .asmx page.
• You upgrade the Web server to Microsoft ASP.NET 2.0.
• You start a client application that uses the Web service.

In this scenario, client applications may not work as expected.

This problem occurs when the XMLElementAttribute attribute has qualified names where the field names are the same, but the namespace is different. This causes the reflection order of the fields in the Enum class to change after you install ASP.NET 2.0. The change in the reflection order may cause a client application not to work as expected.

Microsoft has confirmed that this is a bug in the Microsoft products that are listed in the "Applies to" section.