1. First of all open RUN box by pressing windows and R keys together.
2. Now in the RUN box, type regedit and click OK. It will open registry editor.
3. Now in the registry, navigate to HKEY_CURRENT_USER > Software > Microsoft > Office > 12 > Word and expand it.
(The number 12 might be different as per the version of office installed in your computer)
4. Now you should see "Data" folder there. Just right click on it and delete it.
5. Now open your Microsoft word, it should be rest to it's defaults and you can use it without any problems.
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