Unable to Connect to Marketplace - Curl Missing Error

We were running concrete 8.5.1 and had not connected to the marketplace in a while (was told June 2020). I have upgraded to 8.5.6.
I have checked permissions on `application/files/ , application/config/, packages/ and updates/ and they’re all drwxrwxrwx which I believe is correct.

I checked that all of the following are installed
MySQL (with PDO extensions)
GD Library with Freetype

I tested curl in a separate PHP page (one of the common PHP/curl tutorial sites) and it seems to be working.

I created a new account and a new project, then entered the ID and secret. Though it seems we aren’t getting to that stage.

Are there other things I can check?
Are there specific versions of Curl or other libraries needed? PHP is 7.0 which seems like it should work (though not recommended).

You should never set these permissions on a publicly reachable directory. The last w means that it’s globally writable. For a long, detailed discussion of permissions, please see: https://serverfault.com/a/357109

What is allow_url_fopen set as in your php.ini?

Thanks. I’ll look at those permissions. I just took over for someone retiring and kind of got left with a mess.
Anyway for php.ini
allow_url_fopen = On

@mplagge I missed your reply, sorry!
I’ve updated this page with some troubleshooting tips and things to check. Could you take a look and see if any of those solve your issue? If not, please get back to me with notes on what you tried and what the outcomes were.