I am trying to open a file I downloade from metmania.com, it is a paper model you can print, cut and fold of race cars. I was doing this fine until I switch my default settings to open these files with adobe reader but do not know how to switch back to a program that can read this type of file. Adobe reader says "cant open, file is not supported or has been damaged(for example, was sent in email and wasn't decoded correctly). What program opens this type file? I was doing fine until I changed to adobe reader. You save to temporary file but when I try to open this file I get the error message. How do I open them so I can read or print the material?