How to "sabotage" and make mecbatch.bat fail to run?

Three weeks ago, I managed to learn and made mecbatch.bat work for me. The mecbatch.bat enabled me to run one week's job load over only one weekend! I was proud to announce the "breakthrough" in productivity improvement. However, I can't make the mecbatch.bat work any more. 

What could be the causes?

Do you have any hints?

What I have noticed before I found out mecbatch.bat couldn't work any more were: 1)My Creo session, which had never been closed (because I disabled auto-update function), was closed for some unknown reason/force; 2) An error message popped up when I open Creo session, saying IFX function can't be loaded. My question is how to make "IFX function can't be loaded" happen?

batch run is a basic function.

Thanks.