Hi Joel,
I'm getting the same error, even though Irfanview reads it, as well as my buddy who's running ArcGIS10. I'm wondering if the error is due to the fact that it's a geotiff with coordinate system assigned in the header of the tif.
It's messed up that a Raster based package costing as much as it does isn't kept up to date. Autodesk probably knows about it, but don't hold your breath for it to get fixed with the next version. Historically, they have been slow at updating Raster Design since they don't appear to have a dedicated team designing for it every day.
Randy
