To be very clear about the file, it's
I had this problem with Facetime and, feeling nervous, I just renamed my file to have a .bak at the end. Sure enough, that did the trick. My computer is a year old, but my home directory is much older, having migrated my user from laptop to laptop. At this point, I'm not even sure what files are really necessary any more -- the revocation.plist file has a last modified date in 2006, long before I purchased the current computer.
In the answer you provided (wich is marked as "This solved my question") I have the same things written in Hosts
but I still have that problem
Can you help me?
# Host Database
# localhost is used to configure the loopback interface
# when the system is booting. Do not change this entry.