Parser Error: The base class includes the field XXX, but its type is not compatible

Problem

You get this error when attempting to run your application:

Configuration Error

Description: An error occurred during the parsing of a resource required to service this request. Please review the following specific parse error details and modify your source file appropriately.

Parser Error Message: The base class includes the field ‘XXX’, but its type (‘YYY’) is not compatible with the type of control (‘ZZZ’).

You are running a different version of the .NET Framework than the one for which your application was created.

Solution

Configure the Microsoft IIS server to use .NET Framework 2.0 or later and the application should then run properly.  See these topics for instructions:

Microsoft IIS is Not Installed on Your Machine

Microsoft IIS is Stopped (Not Running)

Running Microsoft IIS 6.0 on Windows Server 2003

See Also

Part VII:  Troubleshooting Applications

Application Will Not Run

Application Runs But No Data is Displayed

Application Error Messages