Hi, I'm trying to run an external method that has a line that runs an os.system command to execute a Java .jar executable that simply outputs a text file as well as prints out a string. I've saved the python script as well as the Java .jar executable in my Extensions folder: /var/lib/zope2.8/instance/plone-site/Extensions/ Here is my Python script: def runYahooSearch2(self): import os homedir = os.getcwd() # on my machine homedir is /var/lib/zope2.8/instance/plone-site command = "java -jar "+ homedir + "/Extensions/test.jar" whatisread = os.popen(command).read() print whatisread This external method is triggered in my DTML code. I've created other external methods before so i know i've done it right.. but the os.system() command for java -jar just doesn't seem to work. I've tried to use other commands such as: os.popen("ls") and it works perfectly Its just this java -jar which does not execute at all... I know it doesn't execute at all cos it doesn't output a file or print the string. If i manually type out into the terminal : java -jar /var/lib/zope2.8/instance/plone-site/Extensions/test.jar it works perfectly But using the external method given above just gives me a blank output. I've also tried popen2: from popen2 import popen2 outputTGT, inputTGT = popen2(command) print outputTGT.readline() and still the jar is simply skipped and not executed. Does anyone know whats the cause and cure for this problem?... Or anynone knows any other method i can use instead of os.popen os.popen2 and os.system to run this command line statement?... or any way i can catch the exception which is being thrown when the java -jar is attempting to run ( if there is any in the firt place) ? Anything would be highly appreciated!... Kinda in a fix right now!... Thanks in advance! Cheers Wan