Yes

In ASP.NET, the web.config file is a fundamental part of the configuration for web applications. It contains settings that define how the application operates, including configuration for things like database connections, session state, authentication, and more.

However, it is technically possible to run a web application without a web.config file. If you do not provide a web.config file, ASP.NET will use default settings for many configurations, which may or may not be suitable for your application’s requirements.

Here’s what you might want to mention in your interview answer:

Default Settings: ASP.NET will use default settings for various configurations if a web.config file is not present. These defaults are generally designed to be suitable for a basic application but might not meet the specific needs of a more complex or customized application.
Limited Control: Without a web.config file, you lose the ability to customize and configure various aspects of your application. This includes settings related to security, session management, error handling, and more.
Potential Issues: Relying solely on default settings can lead to issues such as security vulnerabilities, performance bottlenecks, and compatibility problems with specific features or components your application might require.
Not Recommended for Production: While it may be possible to run a web application without a web.config file, it is generally not recommended for production environments where fine-tuning and customization are crucial for optimal performance, security, and functionality.

So, while it’s technically feasible to have a web application running without a web.config file, it’s not a recommended practice for anything beyond the most basic scenarios. Having a well-configured web.config file allows for better control, customization, and management of your ASP.NET application.