Problem with use of pmode function

Hello, I'm trying to execute an algorithm in parallel mode using pmode.However,after a few minutes (or hours,sometimes),a message saying "...sending a stop signal in all labs... " is displayed in the Command Window,terminating all parallel processes.The termination of the Parallel Processing is done automatically (it seems that it is done by the program itself),without any intervention by me.Could anyone assist me with this problem? Thank you very much in advance...