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Q294217: Cannot Retrieve Custom HTTP Variables That Contain an Underscore

Article: Q294217
Product(s): Internet Information Server
Version(s): 3.0,4.0,5.0
Operating System(s): 
Keyword(s): 
Last Modified: 08-MAY-2002

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The information in this article applies to:

- Microsoft Internet Information Server versions 3.0, 4.0 
- Microsoft Internet Information Services version 5.0 
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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 this to be a problem in the Microsoft products that are
listed at the beginning of this article.

Additional query words:

======================================================================
Keywords          :  
Technology        : kbiisSearch kbiis500 kbiis400 kbiis300
Version           : :3.0,4.0,5.0
Hardware          : ALPHA x86
Issue type        : kbbug
Solution Type     : kbpending

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