I work with a lot of Excel and Word documents and all the documents that appeared in the Frequent column were cluttering my taskbar and I wanted to remove them. Here’s how you can easily check or uncheck to hide or show both Recent and Frequent Items in taskbar.
Right-click on the Taskbar and click Properties
Click on the Start menu tab
Under the Privacy field you will have two boxes
Uncheck Store and display recently opened items in the Start menu and the taskbar
Click Apply then OK
This is pretty straightforward and you can change these settings if you need those files to show on the taskbar again.