Yes I runed roscore before but still not working!! could it be an hardware pb?
... logging to /home/akrem/.ros/log/1eed4b80-dcfc-11e3-a889-d4bed98fa8d6/roslaunch-akrem-OptiPlex-790-3075.log Checking log directory for disk usage. This may take awhile. Press Ctrl-C to interrupt Done checking log file disk usage. Usage is <1GB.
started roslaunch server ros_comm version 1.10.2
SUMMARY
PARAMETERS * /rosdistro * /rosversion
NODES
auto-starting new master process[master]: started with pid [3090] ROS_MASTER_URI=
setting /run_id to 1eed4b80-dcfc-11e3-a889-d4bed98fa8d6 process[rosout-1]: started with pid [3103] started core service [/rosout]
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