DOCUMENT:Q169497  17-JUL-2001  [visualc]
TITLE   :PRB: "Another Application is Currently Using JET File..."
PRODUCT :Microsoft C Compiler
PROD/VER:4.0 4.1 4.2 5.0 6.0
OPER/SYS:
KEYWORDS:kbDAOsearch kbDatabase kbMFC kbODBC kbVC

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The information in this article applies to:

 - Microsoft Visual C++, versions 4.0, 4.1 
 - Microsoft Visual C++, 32-bit Enterprise Edition, versions 4.2, 5.0, 6.0 
 - Microsoft Visual C++, 32-bit Professional Edition, versions 4.2, 5.0, 6.0 
 - Microsoft Visual C++, 32-bit Learning Edition, version 6.0 
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SYMPTOMS
========

When you try to install DAO components, the following error message may appear:

   Another application is currently using JET file, close all applications and
   continue.

CAUSE
=====

This error message can have one of following causes:

 - Another application has opened one of the DAO/Jet DLL's. When a DLL is loaded
   in memory, Windows treats the file on the disk it was loaded from as
   read-only. This is by design.

 - The read-only attribute of the file that is being updated has been turned on.

RESOLUTION
==========

To resolve the first problem, if one of the DLL's that DAO is trying to update
is loaded in memory, then shut down all of your applications and tell the setup
program to continue. It is a good idea to perform a setup with all applications
shut down for this very reason.

The second problem is not as obvious because the setup program cannot distinguish
between a file with a read-only attribute set and a file that is currently
loaded into memory. The setup program will not identify the specific file(s)
that have read-only turned on.

Having the read-only flag set for DLL's is usually used as a low-level virus
protection, but it can also hamper the operation of programs using those DLL's
or attempting to upgrade them. From a DOS command prompt, go to the Windows
directory and type:

      attrib -r *.* /s

You may encounter some files that cannot be set as read-only. As long as they are
not EXE's or DLL's, it is not a problem.

You may also want to go to the \Program Files\Common Files directory and perform
the same procedure because DAO/Jet and other shared components are often
installed there as well.

STATUS
======

This behavior is by design.

Additional query words: kbvc400 kbvc410 kbvc420 kbvc500 kbvc600

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Keywords          : kbDAOsearch kbDatabase kbMFC kbODBC kbVC 
Technology        : kbVCsearch kbVC400 kbAudDeveloper kbVC410 kbVC420 kbVC500 kbVC600 kbVC32bitSearch kbVC500Search
Version           : 4.0 4.1 4.2 5.0 6.0
Issue type        : kbprb

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