I suggest to always use the lates openLCA version (currently version 2.0.2) which might resolve your issue. In 2.0.0 there was a memory leak, which means that the Monte Carlo calculation was using more memory storage in each iteration and potentially shuts down when all of your memory storage is used ... this got already resolved in version 2.0.1. The latest version 2.0.2 and the changelogs can be found here: https://www.openlca.org/download/