Could not sync or add my site

I have tried to sync my site from the Hub and also by installing WPMUDEV Dashboard plugin. When I try to sync from Hub it shows "We hit a snag while auto-installing the WPMU DEV Dashboard plugin on " and when I tried to install the plugin manually and tried to login from the admin it did not work.
It showed 403 error and also suggested
"Is php on my server properly configured to be able to contact with a POST HTTP request via fsockopen or CURL?"
I have contacted my host and they confirmed that it should be fine.