FIX: HTTP Error 403 When Submitting PATH_INFO to Mapped Application

When submitting extra path information to an Internet Information Server (IIS) application that has been mapped to a file extension, an error "403.2 Forbidden: Read Access Forbidden" will be returned to the browser.

This problem can be resolved by loading the hotfix available at the following location:

Microsoft has confirmed that this is a bug in the Microsoft products that are listed at the beginning of this article.

The following URL will execute the CGITest.exe application passing /Extradir/Extra.txt as PATH_INFO. You can map a file extension to the CGITest.exe using the Internet Service Manager. If the mscgi extension is mapped to CGITest.exe, the above URL can be executed as follows: In this case, computers running Windows NT 4 Service Pack 6a will return a 403 error.