If you have tried everything on this list, you can speak with an agent for more assistance.
Troubleshoot Installing and Running TurboTax on Windows
https://ttlc.intuit.com/questions/4711350-turbotax-2018-cd-will-not-install-i-purchased-it-through-a...
Please see this Turbo Tax FAQ will show you the best way to reach an Agent.
https://ttlc.intuit.com/replies/3300041
