The following screenshot is from Word 2010 but the option is located in the same section in Word 2013. In the Display section change the number to Show this number of Recent documents to zero, as shown in the screenshot below.

In Word, Excel or PowerPoint, you can prevent the application from displaying any recent documents. Prevent Office From Displaying Any Recent Documents You can use the same method to manage recent folders in Excel and PowerPoint.There is no option to remove all the folders at once so you will have to remove them one by one. To remove recent folders located in Other Web Locations, right-click the Recent Folders and select Remove from list.You can use the same method to manage recent documents in Excel and PowerPoint.If you go the section where the documents are unpinned you will see the exact same options except that instead of displaying the option Unpin from list you will see the option to Pin to list. The following screenshot shows the option to Unpin from list, which is what you see when you right-click pinned documents. If you want to remove all the documents then select the option Clear unpinned documents. Right-click the document that you want to remove and select Remove from list.The process is same in Office 2010 and Office 2013.

NOTE: Although I am using Word as an example in this article, the same procedure applies to other Office applications, such as Excel and PowerPoint.

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