WordPerfect X3 is just installed on Windows 10. WordPerfect is launched and Document1 cannot be saved to disk. The Save Button is greyed-out. There is no way to select the default file extension, such as *.wpd

This solution has worked for many of us.

In WordPerfect.

Select “Tools” on the top menu bar.

Select “Settings” at the bottom of the drop down list.

Select “Files” from the list of 7 items.

On the “Document” Tab, find the third check box from the bottom which says “Use Enhanced file Dialogs.”

UNCHECK THE BOX that says “Use enhance file dialogs.”

Click the “Apply” button and click “OK” and click “Close.”

Now document files can be saved.

WordPerfect also now appears in Windows 10 File Explorer.