Downloading Adobe Reader on a Windows 7 Laptop

I am a frustrated 75 year old who is not 100% computer literate, but I am somewhat knowledgeable about computers. Having said that, I have never experienced problems downloading Adobe Reader on any previous machine I have had, nor with my current Windows 10 Desktop. However, when I download Adobe Reader on my Laptop, it changes all my desktop icons to PDF, but as they are not PDF documents, I cannot open anything! Is there a way around this problem, of do I have to purchase a product to have adobe Reader work correctly? Thank you