Error: Unknown property: funcname

Hi,

I have defined a MATLAB function which is called by COMSOL. I get an error message such as:

Undefined value found.
- Detail: Undefined value found in the equation residual vector.
There are 2128 degrees of freedom giving NaN/Inf in the vector for the variable mod1.solid.pw
at coordinates: (0.452,0), (0. 448,0), ….

In the meantime, when I try to get a Report from my model in Results/Report, I receive such an error:

Unknown Property
Property: funcname

I think I have properly implemented the MATLAB function (regardless of how it calculates the things for me, because I get the above error).

Does anyone know what this error means?

Thanks,
Jessica