Manual registration of DOI in Crossref failed

[ctgraham]

Interesting that this identical error come from another user as well:

Register DOI with CrossRef

Hi there I get below error when I try the Register button for an unregistered article. If I export the xml file and directly upload to CrossRef it works though. Our server is behind firewall, but I have set http_host and http_port in order to access external network. HTTP/1.0 200 Connection established\r\n\r\nHTTP/1.1 400 Bad Request\r\nContent-Type: application/json\r\nVary: Accept\r\nAccess-Control-Allow-Origin: *\r\nAccess-Control-Allow-Headers: X-Requested-With\r\nContent-Length: 270\r\n…

Might this be an issue with CrossRef?