[Plugin: Facebook Page Publish] Facebook is not reachable from your server:

When I try to use FACEBOOK PAGE PUBLISH, I get the following error.

Facebook is not reachable from your server: Failed to connect to 2a03:2880:2110:3f02:face:b00c:0:1: Network is unreachable
Check your connection!
[Error occured at line 499]
Your connection options could not be validated.

What does this mean?

http://wordpress.org/extend/plugins/facebook-page-publish/