In Adobe Acrobat DC, in Windows 8.1 environment, why do I get this message every time I attempt to open a PDF: "Do you want the following program to make changes to this computer?"

In Adobe Acrobat DC, in Windows 8.1 environment, why do I get this message every time I attempt to open a PDF: "Do you want the following program to make changes to this computer?"

Does anyone know how to avoid this unnecessary message and the delay that it causes?

I have run the repair utility, an no improvement.

Thank you.