Take a look:
1. Article - "Creo Ansys Simulation analysis failed on a specific machine in Creo Parametric": https://www.ptc.com/en/support/article/CS373553
2. Discussion - "There is not enough memory for the Distributed Sparse Matrix Solver to proceed using the out-of-core": https://forum.ansys.com/forums/topic/there-is-not-enough-memory-for-the-distributed-sparse-matrix-solver-to-proceed-using-the-out-of-core/
Delete unimportant files and make the free space in the drive (that your working directory is under it) at least 60GB.
It was a complex problem always failed my simulations. In the end I found out the root cause was such a simple one: there have to be enough free memory space in the workspace in order to run a simulation.
Yesterday I ran 16 simulations overnight, and failed one modal analysis. I found out in the morning that the free memory left in my drive is only 23GB. So I am to delete files or transfer them to outside depository.
Take a look:
1. Article - "Creo Ansys Simulation analysis failed on a specific machine in Creo Parametric": https://www.ptc.com/en/support/article/CS373553
2. Discussion - "There is not enough memory for the Distributed Sparse Matrix Solver to proceed using the out-of-core": https://forum.ansys.com/forums/topic/there-is-not-enough-memory-for-the-distributed-sparse-matrix-solver-to-proceed-using-the-out-of-core/