Windows 98 Compatibility Notes

We have tried to maintain backward compatibility with Windows 98ME in this version. Prior versions are NOT supported. Please bear in mind that this OS is very old, is vulnerable from a security point of view and is no longer supported by Microsoft. We have developed Software Update Wizard 4 using Microsoft's documentation on which API functions are available to Windows 98, but we recommend that you test this release thoroughly if Windows 98 is critical to you.

If you need to support Windows 98, then please bear in mind the following guidance notes with respect to Software Update Wizard usage:

1. The minimum version of shell32.dll running on the target machine must be version 5.0 or later.
2. The version of Windows 98 must be Windows 98 Millennium Edition (ME).
3. You may still use the wuwinstaller.exe redistributable installer described on the deployment page under Windows 98. The calls to install/start the Windows service will, of course, fail, but they will fail without posting error boxes. Similarly, the supplied uninstaller will work correctly under Windows 98.
4. The wuw4.dll WebUpdate()/WebUpdateWait() exported functions will call the Software Update Wizard in application mode if it detects that host operating system is Windows 98ME.