I'm experiencing exactly the same thing on a DNN 4.8 site I installed exactly the same way I've been doing them as usual - this is the first time I've seen this error and so I upgraded to 4.8.1 and then 4.8.2 but no luck  -  I can't view the Host Settings page.

If it were a permission problem surely I'd not be able to see the Admin / Settings page - but I can view that without an error. 

I checked the permissions and then I checked against 14 other sites - varying from dnn 4.5.5 > 4.6.2 > 4.7.  and I have a site which has been upgraded from 3.0.13 >> 4.8.0 that doesn't have this problem. 

I have installed 4.8 three times now with exactly the same error forcing me to look at doing a standard 4.7 build and then upgrading to see if I can't avoid this problem.
What makes it frustrating is that if you're not getting many people complaining about this not much can be done about it, so again, you have to add to your book of ... dnn workarounds ... these notes so you know what you need to do to avoid problems in the future.  So for me, it looks like back to 4.7 and upgrade to 4.8 to see if I can prevent losing the ability to manage the host / settings page becuase unless it's such an important page in the management of your dotnetnuke website.

Nina Meiers
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