All,

I'm trying to run an impact model with SPH strain criteria conversion and a vumat subroutine. I keep getting the error listed in the post's title, and I'm not sure how to fix it. What is confusing me is that without changing anything in the model or subroutine, I can run the model and have it get halfway through before it aborts and that error shows up, but the next time it might abort before even getting to the first odb output increment.

For whatever reason, it seems that when I apply a material orientation to my part, it causes this error to occur, but when the orientation is undefined there is no error. The orientation is simply the global orientation, with the input code shown in the image below. I need the material to be oriented in this way, so I can't just take it out.

A few more notes to help troubleshoot:
- If I turn the SPH conversion off and run the exact same model with brick elements, there is no error.  
- When conversion is on, the error occurs whether conversion is set to 1%, 5%, or 20% strain.
- It is not a disk space or memory space issue, my computer should be able to handle this easily.

Thanks for all the help,

Jack

Abaqus ​​​​​​​