N360 Downloader does not open

i down loaded N360 Downloader from norton.com

I bought n360 standard from staples

n360 downloads but the program will not open.

It also will not open from my downloads files

It works for me. But here is the link from that Norton article to the Microsoft Catalogue with the links to the MS KB noted for SHA 2 Code signing.    https://www.catalog.update.microsoft.com/search.aspx?q=kb4474419

 

Your "LINK" that you send goes to a "page not found"

And have you installed the SHA 2 Code signing update Microsoft KB4474419 from the link I gave above?

 

I have windows 7 ultimate version with service pack 1

Do you have SP1 for your Windows 7 installation? That is a requirement for using Norton 360. 

Also check that you have the Windows update for sha-2 code signing. See this Norton announcement   https://community.norton.com/en/forums/sha-2-code-signing-support-windows-7-0