During my previous quest for an application that can open DOCX files on Windows 98, I came across PolyEdit, a tool which was last updated in 2010 (full version v5.4, portable version 6.0 beta 2). The software installs fine under Windows 98 and seems to have an option for .DOCX inside its File Open dialog:
However, attempting to open any .DOCX file will prompt you to instal Microsoft Office 2007 Compatibility pack, also know as File Format Converter. Because the compatibility pack refused to install on Windows 98, I extracted the MSI from the setup files using 7Zip and used ORCA to modify the installer to remove the OS version check. With this, PolyEdit no longer showed the prompt and attempted to open the .DOCX file, only to show gibberish characters:
I observed the same behavior when using the compatibility pack with Microsoft Office 97 running on Windows 98, and concluded that the compatibility pack, even if installed successfully, for whatever reasons, cannot be used on Windows 98. PolyEdit therefore cannot be used to open .DOCX file on Windows 98. The only way to do this is to use a patched version of Open Office as described in my earlier post.
On Windows XP or later, PolyEdit works just fine with the compatibility pack to open DOCX. It still cannot save .DOCX files – these files must be saved as .DOC or .RTF.
On Windows 98, PolyEdit has no issues open .DOC files from Word 2.0 or Word 6.0 as well as RTF files. It even works well on Windows 95, has tabbed layout, supports tables and even Equation (via MathType). Of course, the editor runs well on my Windows 11. At a size of less than 4MB after installation, it is quite a good lightweight editor for your vintage PCs in my opinion.
You can download the patched version for Windows 98 of the Office 2007 compatibility pack here. If the installer does not start after extraction and complains about no known applications for MSI file, run instmsi.exe to install Windows Installer 2.0 (the last for Windows 98) from the same package. PolyEdit can be downloaded from the official website.