trouble connecting to the hub

This site – We’ve just deleted the old site and set up the new website with a new design and content etc. But when we try to connect to the hub we get this error:

Your server had a problem connecting to WPMU DEV: “”. Please try again.

If this problem continues, please contact your host with this error message and ask:

“Is php on my server properly configured to be able to contact with a POST HTTP request via fsockopen or CURL?”

We don’t usually have problems, we have lots of sited on the hub and they usually work. This site was developed with the domain name and then exported and imported to the new set up if that has any bearing?