This is my problem: Failed to start dynamips Here My Profile System: I have searched a solution for this problem for a whole week. So many ways I tried to fix that, but no luck. Such as: - Fix the path in dynamips tab - Disable Firewall - Login root account to run GNS3 and test >>> still failed. I also tried chmod 777, 666 ... - Try another .bin dynamips file - Remove GNS3 0.8.2 >>> Install GNS3 0.7.4 (follow this advice , but I dont know how to install RC3 Dynamips in this case. Please show me how, maybe it really helps me.) Any answer will be appreciated *Sorry for my English.