Opening EagleCad drawings, Uno pcb.

When I attempt to open the EagleCad files, I get an "Invalid data in file" message. Usinf Version 5.1 EagleCad.

What am I doing whrong????

Eagle is at v7.3 or so these days; I suspect you need a version newer than 5.1!

Up to 7.5 now.