DOCUMENT:Q148745  13-FEB-2002  [visualc]
TITLE   :PRB: DAO Can't Be Used in an ISAPI DLL
PRODUCT :Microsoft C Compiler
PROD/VER::4.0,4.1
OPER/SYS:
KEYWORDS:kbDAOsearch kbDatabase kbMFC kbVCkbbuglist

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-------------------------------------------------------------------------------
The information in this article applies to:

 - The DAO SDK, included with:
    - Microsoft Visual C++, 32-bit Editions, versions 4.0, 4.1 
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SYMPTOMS
========

DAO fails inside an ISAPI DLL. A call to CoGetClassObject() or
CoCreateInstance() for the database engine will fail. You may receive the
following HRESULTS:

E_OUTOFMEMORY                  (    0x8007000EL )
REGDB_E_IIDNOTREG            (    0x80040155L )

CAUSE
=====

DAO wasn't tested or designed to work in an ISAPI DLL. The problem lies within
the way the Internet Information Server handles OLE.

RESOLUTION
==========

Do one of the following:

 - Don't use DAO. Because DAO is non-thread safe, Microsoft recommends that you
   not use it in an ISAPI DLL. The SQL Server ODBC driver works well with an
   ISAPI DLL and is a good choice for scaleable solutions.

   -or-

 - Use the Internet Data Connector feature of the Microsoft Internet Information
   Server to connect to the database file. See the online documentation for the
   Microsoft Internet Information Server for more information about the Internet
   Data Connector.

   -or-


 - Write a CGI application to get to DAO rather than calling DAO in an ISAPI
   DLL.

STATUS
======

This behavior is by design.

REFERENCES
==========

Tech note 67 (TN067), "Database Access from an ISAPI Server Extension"

Additional query words: 4.00 4.10

======================================================================
Keywords          : kbDAOsearch kbDatabase kbMFC kbVC kbbuglist
Technology        : kbAudDeveloper kbDAOsearch kbSDKDAOSearch kbSDKSearch
Version           : :4.0,4.1
Issue type        : kbprb

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