The Default.aspx file is not listed as one of the default content pages in Microsoft Internet Information Services (IIS)
To verify whether the Default.aspx file is listed as a default content page in IIS:
1 In Microsoft IIS Manager, expand the local computer name > Web Sites > Default Web Site.
2 Right-click SAXT, and then click Properties.
3 Click the Documents tab.
4 Locate theDefault.aspx file. If the file is not found, click Add and then type:
Default.aspx
The ASP.NET file is listed as a prohibited web service extension
If the Default.aspx file is listed on the Documents page, the ASP.NET file might be listed as a prohibited web service extension in Microsoft IIS 6.0. To allow ASP.NET web extensions, do this:
1 In Microsoft IIS Manager, expand the local computer name.
2 Click Web Service Extensions or ISAPI and CGI Restrictions depending your version of IIS.