When you click the "Run Analysis" button, APSDS 5.0 uses APSDS32.exe to perform the numerical analysis.

This error is very rare, but the combination of input data that you are using cannot be analysed.

We are currently working on a fix for this problem.

In the interim, try modifying one or more of your parameters such as layer thicknesses or material properties to see if that can be analysed without this error.