Xterm error: No such directory

Dear Fluka Experts,
I am conducting an experiment with PuO2 bombarded by high energy proton. I can execute this experiment with only Plutonium(material), but when I add Plutonium Dioxide (PuO2), the program give following error. I have also tried this with Co2 (other compound-Just for checking), it works. Whenever, I add heavy compounds in Fluka (like PuO2 or UO), it provides the same error.
Please suggest some solution.
Best Regards.

Dear Muhammad,

if you select the 001 under Cycles, you can find the actual output files of FLUKA.
Please check what error messages you find the .err, .log and .out files.

the .core file would contain the memory dump if FLUKA when it crashed, but it is disabled by default. (The file size is zero.)