Why has LibreOffice writer v4.3.0.4 become unassociated with DOC files?

I had it as the default when I double-clicked on a .doc file, and left OpenOffice writer to handle .odt files. That was working fine for a few weeks. But now when I click on a .doc file, nothing happens. Even when I go to the LibreOffice 4 folder and double click on swriter.exe, nothing happens. What’s up with that?

It is likely the file associations in Windows have changed. Please check the operating system settings to ensure DOC files are still associated with LibreOffice.