I just did a full sandbox refresh. Spent a couple hours debugging code before I finally saw where the null pointer was coming from.
In my production org, there's a custom object (position) with lookup to another customer object (order). I have a page to manage these objects and do a bunch of math based on the values of the lookup order.
In my sandbox, where the order auto number would be, I see this:
It's not blank--there's like an underscore character. You can hover on it, or click it and get this message "Data not available"
Anyone ever seen that before? Both orgs are on Spring 13, but sandbox will go to summer 13 this weekend.