Error message when you try to upload an Excel 2007 workbook to an Excel Web Access Web Part in Windows SharePoint Services 3.0: "The request failed with HTTP status 401: Unauthorized."

You add a Microsoft Office Excel Web Access Web Part to a Web page in a Microsoft Windows SharePoint Services 3.0 site. Then, you try to upload a Microsoft Office Excel 2007 workbook to the Excel Web Access Web Part. However, you receive the following error message:

This issue occurs if you configure the Shared Services Provider (SSP) Web application that hosts Excel Calculation Services to use Basic authentication. Excel Calculation Services does not support Basic authentication. By default, Windows SharePoint Services 3.0 uses Integrated Windows authentication.

Configure the SSP Web application that hosts Excel Calculation Services to use Integrated Windows authentication. To do this, follow these steps:

1. Click Start, point to All Programs, point to Microsoft Office Server, and then click SharePoint 3.0 Central Administration.
2. Click the Application Management tab. Then, click Authentication providers under Application Security on the Application Management page.
3. On the Authentication Providers page, click the down arrow in the Web Application box, click Change Web Application, and then click the Web application that you want to configure.
4. Under Membership Provider Name, click Windows. Then, in the IIS Authentication Settings area of the Edit Authentication page, click to clear the Basic authentication (password is sent in clear text) check box.
5. Click to select the Integrated Windows authentication check box. Then, click either Negotiate (Kerberos) or NTLM. Your choice depends on the security configuration that you want.
6. Click Save.

For more information about Excel Services, visit the following Microsoft Web site: