What is wrong with this wall?

[gardendiva]

Kat - Thank you for your input! It sure feels good knowing there are people out there who are willing to offer advice.

I've been struggling with a few issues on my own projects, so I went back to the User Manual and was working thru it. This is the house from the manual so perhaps there was an issue with it. I had issues with the roof, too.

There is a second wall in this same plan that does the same thing from time to time. If I change the specs, the wall fixes itself but as soon as I leave and come back in...same issue...hollow wall. However, the original wall I've never been able to make right. I found a fix for 'hollow wall' in the online support center, but it only pertains to the Pro edition.