Seems like some people has had similar bugs, see this thread. http://world.episerver.com/forum/developer-forum/-EPiServer-75-CMS/Thread-Container/2014/10/Broken-System-Settings-in-7133/
"When looking into the content of EPiServer.Cms.Shell.UI.zip or EPiServer.Shell.UI.zip (under ~/modules/_protected/), I noticed there was a folder named "7.6.4.0", which led me to believe that those files under the _protected folder was not updated when updating the NuGet-packages. Bingo! The content of the "packages\EPiServer.CMS.UI.7.14.0\content\modules\_protected" folder, contained newer files. Manually replacing the files made it working again."
OR
"I've just upgraded from 7.5.394.2 to 8.5 and got the same error as anve in our testenviroment. The solution for me was to remove modules and modulesrepository under my vpp folder. Also make sure there is no mudulesbin under the root folder."
Hi,
I've just upgraded a site from 7.5.++ to the latest on Nuget (9.8.3) and so far all seems to be working with the exception of the menu in CMS Admin mode where I get a null reference exception as follows:
Has anyone else encountered this and know how to fix?
Thanks,
Mark