I'm having the exact same problem. Non of the mentioned suggestions worked for me.
Hey Peter, I was able to get it to work. Here's the trick that I used:
1) first, select one of the standard isotropic materials from the default solidworks material library.
2) now, change the properties for this material to orthotropic
3) next, change the material to your custom orthotropic material
This works for me. It's really a buggy part of the software and in my opinion, it does not work anywhere near as smoothly as what I would expect from a software company like this!
One last tip - when you create your new material, you can start by copying an existing material and then modifying the properties to suit your needs. This seems to help out as well.
Hope this helps!
I'm having the same problem trying to set up an elastic-plastic material: it always seems to revert to Linear elastic isotropic even after I Save and Apply the changes
alan, might be worth opening a thread with your info and link to this one for reference.
is this happening for all models?
what version/service pack are you on?
what is the workflow?