Well, then it is very hard to say what is going on.

Several reasons maybe.

#1 the materials are simply too old - Vue 3.1 or older. Then only Vue 5 can read them. Newer versions not. You can try to convert them with the scene converter that comes with Vue on the CD (or iso). But try it only on copies, bever on originals.

#2 There come orginally from objects that were bought at Cornucopia and were taken from copy-protected object. Then the materials are protected too and you will not be able to read them.

#3 The bitmaps that are used are either missing or can't be read. Then you maybe are unable to read the whole material as well.

By any reason the names ring a bell - my guess is that the materials are simply too old.

One day your ship comes in - but you're at the airport.