If you turned the Recent Documents feature OFF, then you'll need to turn it back ON in order to start seeing recent documents again.
To start seeing documents in your Recent Documents list again, just repeat the same steps above, but instead of entering a "0" (zero), enter the number of documents you want to have displayed. You can enter up to "50" in this box, but Word will only display as much as it can fit on your screen. For most people, that's about 17 documents.
To designate specific documents to remain in the Recent Documents list, just click on the "pushpin" icon next to the document. The documents that you specify with the pushpin will remain on the list until you remove it by clicking the pushpin icon again.

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