How to Fix WebForms UnobtrusiveValidationMode requires a ScriptResourceMapping for jquery Error in ASP.NET Web Forms

Introduction

While working with ASP.NET Web Forms, many developers face the following error:

WebForms UnobtrusiveValidationMode requires a ScriptResourceMapping for 'jquery'. Please add a ScriptResourceMapping named jquery (case-sensitive).

This error usually appears when:

You create a new Web Forms project
You update Visual Studio
You use validation controls like RequiredFieldValidator
jQuery is not properly configured

In this article, we will understand:

Why this error occurs
Where it occurs
How to fix it step-by-step
Alternative solution
Best practice for beginners

Why This Error Occurs

ASP.NET Web Forms uses something called:

👉 Unobtrusive Validation

Unobtrusive validation depends on:

jQuery
jQuery Validation libraries

If jQuery is not registered properly in the project, this error appears.

When Does This Error Appear?

This error usually appears:

When you run the project (F5)
On pages that use validation controls like:

<asp:RequiredFieldValidator>
<asp:RegularExpressionValidator>
<asp:CompareValidator>

This is the simplest solution.

Step 1: Open Web.config File

Go to:

YourProject → Web.config

Step 2: Find `<appSettings>` Section

If it does not exist, add it.

Step 3: Add This Code Inside `<appSettings>`

<appSettings>
<add key="ValidationSettings:UnobtrusiveValidationMode" value="None" />
</appSettings>

Step 4: Save and Run Project Again

What This Code Does?

This line:

ValidationSettings:UnobtrusiveValidationMode = None

It disables unobtrusive validation.

So now:

jQuery is no longer required
Validation works using traditional method
Error disappears