If you use our binaries on a Mac and when running ./factomd you get this error:
13:32:03 2015-10-08 [ERR] BTCD: Unable to start server on [:8108]: 'fe80::1%lo0' is not a valid IP address
It's because of an entry in your /etc/hosts file, usually the last entry as below:
127.0.0.1 localhost
255.255.255.255 broadcasthost
::1 localhost
fe80::1%lo0 localhost
This happens on Macs that have been upgraded over the years. A fresh build or a new Mac with Yosemite doesn't have that entry.
By removing the last entry factomd works fine.
We are looking at a workaround for the installer but for the time being removing "fe80::1%lo0 localhost" should fix the issue.
If you are not aware what the hosts file is better if you don't touch it, in that case wait for an update to our binaries.