Can't connect WPMU dashboard to my WordPress set up.

I am trying to connecting wpmu dashboard in my wordpress. The set up it showing error:

Your server had a problem connecting to WPMU DEV: “cURL error 28: Operation timed out after 15001 milliseconds with 7756 bytes received”. 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?”