There is likely a problem with the inputs. Please review the troubleshooting and tutorial help below first.
Galaxy FAQs: My job ended with an error. What can I do? https://galaxyproject.org/support/tool-error/
Galaxy tutorials: https://galaxyproject.org/learn/
Then if you cannot determine the problem, a bug report can be sent in if working at Galaxy Main https://usegalaxy.org or can reproduce the problem there.
Thanks! Jen, Galaxy team