ITunes problem 64-bit downloading?

I recently downloaded iTunes 64-bit (I'm certain it is 64 bit), and the download is successful. So when I open up iTunes, I connect my iPhone 5c to my computer. The second I connect my iPhone, a popup on iTunes says:
"This iPhone can't be used because the required software is not installed. Run the iTunes installer to remove iTunes, then install the 64-bit version of iTunes."
I know for sure I have downloaded/installed the 64-bit version?

I downloaded from this link http://www.filehorse.com/download-itunes-64/

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