WPMU DEV Dashboard > Remote HTTP Requests FORBIDDEN

Hello there,

I have a client where the WPMU DEV Dashboard has worked fine until now. I guess there is something on the server, but I have multiple installs on the same server without problems.

I had trouble getting to the settings as the only visible menu items was (and still is) 'Dashboard', 'Support' and 'Manage'. When selecting 'Dashboard' it told me that I was a 'Free member' and had to upgrade. I did not find anywhere to set my username and password to fix this, so I typed the path to 'admin.php?page=wpmudev&clear_key=1' and was then able to set my credentials.
But when I sign in, 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?"

When I check out the Support/System Info page, it tells me that WPMU DEV: GET and WPMU DEV: PUT is FORBIDDEN..

If I move the whole site over to my local computer, everything work just fine - so the problem must be the server, not my wp/plugins/other..

PS! The only thing I had to fix to make it run on my local computer was to remove a few lines of 'AddOutputFilterByType DEFLATE' from the .htaccess file.

How can I fix this?