OLEXP: "Msimn.exe Is Not a Valid Win32 Application" Error Message When You Start Outlook Express 5 (310880)


The information in this article applies to:

  • Microsoft Outlook Express 5.01 for Windows 98 Second Edition
  • Microsoft Outlook Express 5.0 for Windows 98 Second Edition
This article was previously published under Q310880
For information about the differences between Microsoft Outlook and Microsoft Outlook Express e-mail clients, click the following article number to view the article in the Microsoft Knowledge Base:

257824 OL2000: Differences Between Outlook and Outlook Express

SYMPTOMS

When you try to start Outlook Express version 5, the program may not start, and you may receive the following error message:
C:\Program Files\Outlook Express\Msimn.exe is not a valid Win32 application

RESOLUTION

To resolve this issue, extract the Msimn.exe file from the Windows 98 CD-ROM or from the Windows .cab files on the hard disk, and copy the Msimn.exe file to the Outlook Express folder. Follow these steps:
  1. Make sure that the Windows 98 Second Edition CD is in the CD-ROM drive or that the Windows .cab files are available on the hard disk.
  2. Click Start, and then click Run.
  3. In the Open box, type sfc.exe, and then click OK to start the System File Checker utility.
  4. In the Select an option and click Start list, click Extract one file from installation disk, type msimn.exe in the box, and then click Start.
  5. In the Restore from box, type the path to the CD-ROM drive. For example, if your CD-ROM drive is drive D, type d:\win98, and then press ENTER.
  6. In the Save file in box, type C:\Program Files\Outlook Express, and then click OK.
  7. To back up the existing file before overwriting it, specify a location to save it to, and then click OK. To bypass backing up the file, click Skip.
  8. When a message tells you that the file has been successfully extracted, click OK.
  9. Quit the System File Checker.
  10. Try again to start Outlook Express.
Modification Type:MajorLast Reviewed:6/30/2004
Keywords:kberrmsg kbnofix kbprb KB310880
©2004 Microsoft Corporation. All rights reserved.