Have you made the DNS changes that were suggested by the error messages?
Code:
Setting defaults...
No results returned for A lookup of localhost
Checked nameservers:
127.0.0.1
DNS ERROR resolving localhost
It is suggested that the hostname be resolveable via DNS
DNS ERROR resolving MX for localhost
It is suggested that the domain name have an MX record configured in DNS
Done
That indicates you have a DNS problem, set-up the correct records and run the install again. Is this a new install or an upgrade?