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Right-click on the Start button (lower-left corner on the taskbar)
Choose Apps and Features
Select Mircrosoft Office from the list of apps, and select Modify
Choose Repair from the popup window and click on Continue
Follow the instructions on the screen to complete the repair
Restart your machine
Note: Performing this action will repair the entire Office suite even if it’s just one application you want to repair such as Word or Excel.
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