Hi William
I'm not with Laminar Research, just a fellow simmer in the UK, but can I assume that you are trying to install X-Plane 11 by DVD and it is Disk 5 that does not load during the install?
Presumably you have access to the internet in order to submit your Q&A post and if you do, then the best thing to do is download X-Plane 11 from the Laminar Research website and use the Product Key from you DVD set to activate it.
Regards