Teachers are telling your their Preferences have changed, but they aren't making the changes.
It's possible someone on your administrative staff has made those changes. If an Administrator goes into Staff Setup in SchoolLogic, selects a teacher, clicks the TeacherLogic XE link, opens any class, goes to Gradebook Preferences > Miscellaneous and makes any change, the change affects all teachers -- even though it might appear to the operator he is changing only the Preferences of the teacher he opened.
You should be able to prevent future changes by going into Logic Admin, and then:
1. Click TeacherLogic XE in the top horizontal bar;
2. Click Administrator in the left, vertical bar.
3. Click Restrict to Read-only.
4. Click Submit.