Turbo Tax downloading to LR CC

It sounds like one of the files in the Turbo Tax download has an extension that is mapped to LrC. Here's an article to check file extension mappings to their associated app. https://www.lifewire.com/how-to-change-file-associations-in-windows-2624477

Okay, more detail is needed.

I am trying to download Turbo Tax but when I do, LR CC keeps poping up. 

Downloading software doesn't cause anything to pop up. Did you install TurboTax? Did you try to open TurboTax? If so, did the installation seem to work properly? If so, did you double-click on the TurboTax icon? At what exact step does Lightroom pop up?

That's a new one. I would try the setting in Preferences -> General -> Import settings: Uncheck the "Show Import Dialog When Memory Card Detected". Have no other ideas.