ASP.NET is part of the .NET framework as the System.Web namespace. In order to use ASP.NET, you must have the .NET Framework installed on the computer that hosts your ASP.NET Web sites. You can download version 2.0 of the .NET Framework from .NET Framework Developer Center web site.

For more information, see ASP.NET Overview.

You can create ASP.NET pages and classes using any text editor, such as Microsoft Notepad, which comes installed with Microsoft Windows. However, Microsoft Visual Studio and other integrated development environments (IDEs) offer many programming features, such as page templates, IntelliSense, code auto-completion, and design-time compilation. These features can speed up the development process and provide organization for your project. For more information about Visual Studio, see the Visual Studio Developer Center.

In order to work with an ASP.NET Web application, you must use a browser to make requests to the Web server that hosts the application. ASP.NET Web applications are typically hosted using IIS as the Web server. You can test applications by running IIS locally on your computer or by deploying pages and components to a shared server.

Note
If you are using Visual Studio, you can test ASP.NET Web pages using the ASP.NET Development Server, which runs pages locally on your computer without requiring you to install IIS.

To work with IIS as a Web server, the user account under which you are running must have permission to write to the directory where the application resides, whether as a child of the Web server root (typically the Wwwroot folder) or as a virtual directory. Note that the account that requires permission for an application directory is typically different in design time than in run time. By default, ASP.NET Web applications run in the context of a local machine account named ASPNET (for WindowsВ 2000 and WindowsВ XP), or in the context of the NETWORK SERVICE account (for Windows ServerВ 2003). For more information, see ASP.NET Required Access Control Lists (ACLs) and ASP.NET and IIS Configuration.

Note
If you have IIS installed, installing the .NET Framework registers the ASP.NET ISAPI extension (Aspnet_isapi.dll) in IIS. If you install IIS after the .NET .NET Framework is already installed, you must use the Aspnet_regiis.exe utility to register ASP.NET with IIS. For more information, see ASP.NET IIS Registration Tool (Aspnet_regiis.exe).

If you are not able to install IIS locally on your development environment, you can develop your application using a shared IIS Web server. In this scenario, the same permission requirements apply as in the local IIS scenario.

If your application involves data storage, you need to have access to a database application, such as Microsoft SQL Server, and you must have the appropriate permissions to read and write data to the database. In typical scenarios, one account is used to access the database in design time and a different account is used to access the database in run time. By default, ASP.NET Web applications run in the context of a local machine account named ASPNET (for WindowsВ 2000 and WindowsВ XP), or in the context of the NETWORK SERVICE account (for Windows ServerВ 2003). For more information, see ASP.NET Data Access Overview.

Additionally, some ASP.NET features, such as membership and profile properties, require a database. For more information, see Introduction to Membership and ASP.NET Profile Properties Overview.

In order to send e-mail messages from an ASP.NET Web application, the application must be able to forward the messages to an SMTP server. Some ASP.NET controls, such as the PasswordRecovery control, require the ability to send e-mail messages.

You can use the IIS SMTP virtual server to forward e-mail messages. For more information, see How to: Install and Configure SMTP Virtual Servers in IIS.