We updated the server platform last Sunday (application and web server components). No issues. But today, a user reported they were unable to view cases on their dashboard or anywhere else. It appears to be a bug in the platform software and I am working with the vendor for a resolution. The issue manifests when the investigator is in the "Investigator" role with the Options set to "1" or blank. Only a Manager can view or change these settings.
You can workaround this issue by setting any affected investigator to Option "2" or making them a Manager.
I think this is a case of something getting broken during modifications to the vendor's platform, and should be resolved very soon as they typically push a patch right away for something like this.