Hi Jeff,

I don't know why this is happening... I just updated comets as
well, and got an orbit showing C/2007 W1 where it ought to be.
A couple of things to check:

Are other things in the solar system (asteroids, planets,
artificial satellites) where they ought to be? If everything
is off, that suggests your viewpoint (set in the Locations dialog)
might be someplace other than Earth.

Are you using the current update from

http://www.projectpluto.com/new.htm

?

And if there are still problems, I'd recommend e-mailing me
the file 'comets.dat' from your Guide folder. I'd be interested
to see if perhaps that has become corrupted. I've heard of two
cases over the last year in which this happened. I have no clue
as to how either one occurred. Maybe the third case will cause
a pattern to emerge (and a fix to be determined).

-- Bill