Preupgrade: Anaconda can't find upgrade root?

[Richard Shaw]

I tried using preupgrade to upgrade my F15 64bit to F16 and ran into
an issue with anaconda.

It gave me a somewhat confusion error:

https://plus.google.com/photos/112912133662927916698/albums/5692032713007961425?authkey=CJmNmIWD6M7WHQ

Or, if you want to skip the picture link:
---
Title: Upgrade root not found

The root for the previously installed system was not found
---

So which is it? The title says the upgrade root isn't found but the
contents say the root of the previously installed system was not
found...

Thanks,
Richard