What won't load? The CD program or you can't open your 2016 return in it? If you finished 2016 in the Online version you should be able to just print it out now and mail it.
Don't think you can buy the 2016 CD now, they only sell the downloads for prior years. So did you buy 2016 or the 2018 CD?
Did you buy 2016 here?
https://turbotax.intuit.com/personal-taxes/past-years-products/
Access your downloads here
https://shop.turbotax.intuit.com/commerce/account/secure/login.jsp?pagecontext=download
How to download your software purchase
https://ttlc.intuit.com/community/installing/help/how-do-i-download-the-software-i-purchased-at-turb...
