INFO: Quick Guide to Setting Up the OEM Preinstall Kit (OPK)


Original equipment manufacturers (OEMs) and system builders use the Microsoft OEM Preinstall Kit (OPK) to preinstall Windows operating systems. This article describes the process of extracting the tools from the OEM CD-ROM.

NOTE:This information is for the benefit of OEMs and system builders who have special license agreements with Microsoft to use the OPK.


The OPK is shipped with every Windows 95 and Windows 98 OEM CD-ROM. They are present under the \Tools folder in Windows 95 and the \Tools\Admin folder for Windows 98. The following allows system builders to set up the Preinstallation Wizard on the reference computer. Using the Preinstallation Wizard and the Windows product CD-ROM, it is possible to preinstall the Windows 95 or Windows 98 operating system for different computer models.
With the Preinstallation Kit, you can:

  • Customize the Windows 95 or Windows 98 startup screen to show a company’s logo.
  • Customize the dialog box for the System application in Control Panel to show the company's logo and support information.
  • Deliver a ready-to-use system by preinstalling and testing all the applications on the customer’s system, including updated drivers and patches.
  • Configure the Internet Explorer Favorites list to include the company’s Web site.
  • Save time preinstalling Windows operating systems because the process is automated.
For more details on the preinstallation process, please refer to the Windows 98 System Builder Preinstallation User’s Guide on the OEM compact disc. There is a Help file provided in the System Builder Wizard.

NOTE:To get up-to-date information and support for preinstallation of Windows 95 and Windows 98, see the Microsoft OEM System Builder Web site:

If you aren’t registered with this Web site, visit:

Install and Run the Preinstallation Wizard

The first step in the preinstallation process is collecting information about the computers on which you plan to preinstall, your installation process, and your branding information. This information is stored in a set of files called a configuration set. You can duplicate a configuration set and edit it for all the different model systems you ship.

To create the wizard folder:
  1. Insert the Windows 95 or Windows 98 SB CD-ROM into the CD-ROM or DVD-ROM drive of the reference system. If prompted to update the system, click No.
  2. Click Start, point to Programs, and then click MS-DOS Prompt.
  3. At the command prompt, switch to the \Tools\ folder on the OEM CD-ROM for Windows 95 versions. For Windows 98 versions, switch to the \Tools\Admin folder of the OEM CD-ROM.
    For example, if your CD-ROM drive is drive D, type D: at the command prompt after placing the OEM disc in the drive. Then, type Cd\Tools\Admin and press ENTER to switch to the Admin folder.
  4. At the command prompt, type the following command, including the quotation marks and spaces, and press ENTER:
    mkcwrt /C:" /C mkcwrt.bat <CD-ROM drive letter><drive/path>"

    <CD-ROM drive letter> is the drive letter of your CD-ROM or DVD-ROM drive,
    <drive/path> is the drive and path where you want to install the wizard and its support files.

    The letter D is used for the CD-ROM or DVD-ROM drive. (If your CD drive is not D, replace it with the appropriate drive letter.)

    For example:
    mkcwrt /C:" /C mkcwrt.bat D: C:\wizard"
    The Preinstallation Wizard is extracted into the C:\Wizard folder. When the extraction is complete, the command prompt reappears.
  5. Click Start, point to Programs, and then click Windows Explorer.
  6. Locate the Wizard folder you just created, which contains the Opkwiz.exe application file.
    You are now ready to start using the System Builder Wizard. Refer to the Microsoft Windows 95 or Windows 98 System Builder Preinstallation User’s Guide in the Wizard folder for more information.
In addition, you can find an online version of the Microsoft Windows 95 or Windows 98 System Builder Preinstallation User’s Guide, hot tips and tricks, and frequently asked questions at in the Technical Support section.


For additional information, click the article number below
to view the article in the Microsoft Knowledge Base:

184978 PRB: Error Messages when Running Mkcwrt from Command Line