New installation of 2.3.1 - Cant download Packages

I've just installed new version of 2.3.1 to my server. No issues there - everything went smoothly. Manager works fine as well.

However, it just seems to hang when I try to install packages. I just get the loading pop up box and nothing happens.

I've checked all the directories and changed them to 777 but no change.

Does anyone know what I can do?

Thanks

https://forums.modx.com/thread/92183/unable-to-download-extras-modx-2-3?page=3#dis-post-506037