DOCUMENT:Q182059  04-FEB-2000  [iis]
TITLE   :Cache ISAPI Application Option Causes ASP to Return Error
PRODUCT :Internet Information Server
PROD/VER:winnt:4.0,5.0
OPER/SYS:
KEYWORDS:

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The information in this article applies to:

 - Microsoft Internet Information Server 4.0 
 - Microsoft Internet Information Services version 5.0 
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SYMPTOMS
========

It is possible to configure the way that Microsoft Internet Information Services
(IIS) caches Internet Server Application Programming Interface (ISAPI)
applications. Changing the default selection from caching ISAPI application to
not caching ISAPI application causes IIS to return the following error to the
browser when an Active Server Page (ASP) is executed on the server:

   The requested resource is in use

CAUSE
=====

This setting can be changed from the Web Site properties by selecting
Configuration on the Home Directory tab. In Application Mappings there is a
checkbox for the Cache ISAPI Applications option. Changing this selection
modifies the default behavior of IIS . This option is for non-production testing
only.

If the Cache ISAPI Applications option is deselected, IIS does not cache ISAPI
applications. All ISAPI applications are loaded and unloaded from IIS memory
immediately after the ISAPI application is executed on the server, including
ASP. ASP sets up application and session state object and variable that must be
gracefully unloaded from memory. ASP returns the error when it is being unloaded
from memory and an ASP page is attempting to execute. When ASP is loaded and
unloaded from memory, an event is logged in the Windows NT Application event
log. Event ID of Event 3 "Service started" and Event 4 "Service stopped" will be
logged every time ASP is loaded or unloaded from memory.


MORE INFORMATION
================

This behavior is by design. Microsoft welcomes suggestions or comments about
changes in functionality and product design. You are invited to submit
suggestions by filling out the form at the following Microsoft Web site:

http://www.microsoft.com/regwiz/regwiz.asp

Additional query words:

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Keywords          :  
Technology        : kbiisSearch kbiis500 kbiis400
Version           : winnt:4.0,5.0
Issue type        : kbbug
Solution Type     : kbpending

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