where $interface is your interface, i.e.: eth0, p3p1, etc.
Contains old MAC address of the interface, but the script file exists, therefore conflict in configuration.
ie.: Service tries to use detected setings, but ifcfg script exists, therefore "File exists" error.
Fix the MAC address in the script file, with MAC address from:
--> If I find better solution, than fixing by hand, I may update this post.