No, actually is sounds like you probably have a DNS issue.
1. Write down the IP addresses of the DNS server(s) one or more of the computers that work.
2. Write down the IP addresses of the DNS server(s) on your "common router". And your (DSL modem? Cable modem? Other?)
3. Now look at /etc/nsswitch.conf.
Make sure "host" is includes "dns":
4. Finally, look at /etc/resolv.conf.
Make sure one or more of the "known good" DNS IP addresses appears at the TOP of the list.
'Hope that helps .. PSM
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