Cannot Retrieve Custom HTTP Variables That Contain an Underscore (294217)



The information in this article applies to:

  • Microsoft Internet Information Server 3.0
  • Microsoft Internet Information Server 4.0
  • Microsoft Internet Information Services 5.0

This article was previously published under Q294217

SYMPTOMS

IIS cannot retrieve custom HTTP header variables that contain an underscore following "HTTP_" (for example, "HTTP_SM_TESTVARIABLE"). The value returned for the header variable is NULL.

CAUSE

Any underscore ( _ ) that follows "HTTP_" is incorrectly converted to a dash when IIS attempts to retrieve the custom header value for the variable, and therefore, the variable is not found.

WORKAROUND

Do not use an underscore in the custom HTTP header variable name.

-OR-

Retrieve and parse the HTTP_ALL header variable for the custom HTTP header variable.

STATUS

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

Modification Type:MinorLast Reviewed:7/14/2004
Keywords:kbbug kbpending KB294217