not able to open word files

Try this order for Word on Windows when files fail to open and Word shows an error:

1. Update Office
   • Open any Office app.
   • Go to File > Account.
   • Under Product Information, select Update Options > Update Now.
   • If Update Now is not available, select Enable Updates first.
2. Start Word in Safe Mode to check add-ins
   • Open Run.
   • Type winword /safe and press Enter.
   • If Word opens, go to File > Options > Add-Ins.
   • In Manage, select the add-in type and choose Go.
   • Clear add-ins one at a time, select OK, and restart Word normally.
   • Older add-ins such as ABBYY FineReader and Dragon Naturally Speaking are known to cause problems.
3. Run an Online Repair of Office
   • The built-in Repair Now option is often ineffective.
   • In Windows, open Settings > Apps.
   • Find Microsoft Office.
   • Select Modify > Online Repair.
   • This is more thorough and can reinstall Office as part of the repair.
4. Restart the PC after repair
   • If repair was already tried from the error dialog, run Online Repair from Windows Settings instead.
5. If Word opens but a specific file still fails
   • In Word, select File > Open > Browse.
   • Select the file.
   • Select the arrow next to Open and choose Open and Repair.
6. If the file says it is locked for editing by another user
   • Close all Word windows.
   • Open Task Manager and end all Winword.exe processes.
   • Browse to the folder that contains the document.
   • Delete the owner file that starts with ~$ for that document.
   • Open Word and try the document again.
7. If double-clicking files opens the wrong app or does nothing
   • Open Control Panel > Programs > Programs and Features.
   • Select the Office product and choose Change.
   • Run Quick Repair for file association issues.
   • If needed, manually set the correct default app in Control Panel > Programs > Default Programs.

If the problem started after a recent Office update and Office 2016 was installed by MSI, installing KB4018295 is the documented workaround for the known issue with KB4011730.

References:

• Word is not working. - Microsoft Q&A
• Word not opening - Microsoft Q&A
• word is not opening - Microsoft Q&A
• Open a document after a file corruption error | Microsoft Support
• "The document is locked for editing by another user" error message when you try to open a document in Word | Microsoft Support
• Double-clicking an Office file fails to open it in the correct Office program | Microsoft Support
• After installing KB 4011730, you may not be able to open or save Word documents | Microsoft Support