Upgrading from F16 to F17 fails

[JD]

It fails after it displays that the installed fedora 16 will be 
upgraded, and I click next.
I filed the bug with redhat bugzilla but when I logged in to my bugzilla 
accout
I do  not see the bug listed in "My Bugs" list.

I ran the self check for the DVD and it passed. I
checked the sha256 sum of the iso downloaded
and it checked out just fine with the contents of
the  Fedora-17-i386-CHECKSUM file.

The failure to upgrade is repeatable in exactly the same way.

It seems that when I click Next to proceed with the upgrade,
it crashes and dumps the stack. The stack shows that it was
trying to unmount the root dir of the currently installed fc16,
and it failed to do that, and bailed out.