Unwanted caching in MVC application - asp.net-mvc

Question

I have an issue with caching and have tried every solution I can find!
I have a simple create screen where one row is inserted in a table (although I also get the same issue when editing existing rows).
When the row is created, the user is returned to the previous screen, which still shows the old data. (same issue with edit)
Refreshing the page makes no difference. Difference browsers have the same problem. The data is successfully added in the database. Only by restating the application does it refresh the data on screen.
Things I have tried:
1:
DataContext.Refresh(RefreshMode.OverwriteCurrentValues)
2:
[OutputCache(NoStore = true, Duration = 0, VaryByParam = "*")]
3:
ModelState.Clear()
None of which made any difference. I've not had this problem before with edits or creates, so I must be missing something. Any help much appreciated!
The following is the relevant parts of the controller:
ISISDataContext db = new ISISDataContext(StudentISIS.Properties.Settings.Default.ISISConn.ToString());
public ActionResult Index()
{
var student = (ISIS2Models.Student)Session["CurrentUser"];
return View(student);
}
public ActionResult STGCreate(int id)
{
var enrolment = db.Enrolments.Single(e => e.EnrolmentID == id);
return View(enrolment);
}
[AcceptVerbs(HttpVerbs.Post)]
public ActionResult STGCreate([Bind(Exclude = "Id")] StudentGrade STGToCreate, FormCollection collection)
{
var STG = new StudentGrade();
STG.Grade = collection["StudentTG"];
STG.EnrolmentID = int.Parse(collection["Enrolment"]);
STG.DateChanged = DateTime.Now;
db.StudentGrades.InsertOnSubmit(STG);
db.SubmitChanges();
return RedirectToAction("Index");
}
Edit:
Here is the code from the index view which loops through enrolments to show the grade:
<%foreach (var en in Model.Enrolments) {%>
//Some table stuff
<td>
<%try
{ %>
<%= Html.ActionLink(en.StudentGrades.Grade,"STGEdit",new {controller = "Progress", id = en.StudentGrades.StudentGradeID})%>
<%}
catch (NullReferenceException) {%><%= Html.ActionLink("Set","STGCreate",new {controller = "Progress", id = en.EnrolmentID})%><% } %>
</td>
//Some more table stuff
<%}%

Answer 1

Where do the rows come from? is it your ISIS2Models.Student class? I can only assume it is because you have so little code in your Index method.
If it is, and you are storing that in the session, then you are not updating that value, so when you retrieve it from within Index it will still have the same old values.
What you need to do is get the updated model from the database each time you make a call to Index. Some method like this:
public ActionResult Index()
{
var currentUser = (ISIS2Models.Student)Session["CurrentUser"];
var student = GetStudentById(currentUser.ID);//this will get the up-to-date student record from the DB
return View(student);
}