Remote HTTP Requests FORBIDDEN

Hello, when i try to login at my WPMU DEV Dashboard I receive the message:

Your server had a problem connecting to WPMU DEV: "403 Forbidden" Please try again.
If this problem continues, please contact your host and ask:
"Is php on my server properly configured to be able to contact https://premium.wpmudev.org/wdp-un.php with a GET HTTP request via fsockopen or CURL?"

, maybe a problem about whitelisting?