job failed during launch process when submiting a CASTEP job

Dear all:

         There is a serious problem that embraced me a long time,I try my best but still can't find the solution.

         Recently when I submit a CASTEP job, it immediately failed and gave me a note read: job failed during launch process... open log file now?

  when I opened the logfile,there was a note read:filename.xsd and filename.txt does not exist.

         I checked my license server and gateway and found all that were working problely. In additiona,I tried to run a Dmol task and it was ok,unlike the CASTEP module.

         I really can't solve this problem,is there anybody can help me?