Understanding ASP.NET 4.0 Request Validation Changes
When upgrading web applications from .NET 2.0 to .NET 4.0, developers often encounter unexpected validation errors that can be puzzling and frustrating. These errors typically manifest as HttpRequestValidationException messages, indicating that the application has detected potentially dangerous request data. This change in behavior represents a significant shift in how ASP.NET handles request validation, with important implications for application security and functionality. The Validation Challenge The error message you’re likely seeing looks something like this: ...