Please add : (new Sitecore.SecurityModel.SecurityDisabler())
EditContext containts next lines of code :
public EditContext(Item item)
{
Assert.ArgumentNotNull((object) item, "item");
this._item = item;
this._item.Editing.BeginEdit();
}
so you don't need here if you have in your code item.Editing.BeginEdit();
your code must be :
using (new Sitecore.SecurityModel.SecurityDisabler())
{
item.Editing.BeginEdit();
try
{
//Value is updated here from "" to Test
item.Fields["Content"].Value = "Test";
}
finally
{
//item.Fields["Content"].Value is "" again.
// Remove AcceptChanges I never use it , for editing .
// item.Editing.AcceptChanges();
item.Editing.EndEdit();
}
}
I updated my answer, did you check on content editor if are any changes ? Can you clear cache, and check again. It's really strange why is not working I guess can be a caching problem .