Open a Excel workbook.
In the left of the top menu, go to File.
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On the left, click on Options.
You get this new window:
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On the left, select Add-ins.
Then at the back select COM add-ins.
Then click on the Go… button.
You get this new window:
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Thick the Plinxl check-box.
Click the Remove button.
Close excel.
Go to the Windows Apps manager.
Find Plinxl:
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Click on Uninstall.