Problem opening solid.prt file in V28 or V30

I can’t open a solid.prt file in either V28 or V30.
The customer resent it as an igs , and it opened up fine.
Any ideas what could be going on ?

Hi and Welcome,

I think the issue is, that the solidworks file you are trying to open is from a newer version of Solidworks that V28 or V30 can open.