I am also having this problem with a file, I have been converting shape files for a project for the past few days, and now one of them will not work.
Failed to add Layer Package(s) ...(Invalid File)
I can add the layer package into ArcGIS 10 no problem, it is from a 9.3.1 database, has the proper coordinate system.. now I am stumped.
I have attached the layer package, can anyone help?
Thanks
Tina