Chem3D MM2 Molecular Dynamics

Hello!

I would like to run a MM2 Molecular Dynamics calculation with Chem3D 15.1.
In the Dynamics tab I'm using the default settings.
In the Job Type tab I checked the boxes for:
- Setup new Atom Types before Calculation

- Setup ne Atom Charges before Calculation

- Show Step Information 1

- Copy Measurements to Output Box

With these settings the calculation is running.

But if I choose also "Save Step Data In:" I get the error message "The 'Minimum Gradient' value must be >0.".

What could be the reason for that?

Thanks in advance for answers!