Good People, >> >>sudo nmap -sP -n 192.168.1.0/24 -oG - > \ >> /home/hippie/projektarbeit/java/activeHosts.txt >> >this is working if i execute nmap in a shell but not if i call the nmap >command from my java program :( Check the process owner of java. Perhaps it is not the same as stema. Regards, Mridul.