After setting up the HTTP Event Collector on a heavy forwarder, why am I getting error "token is required" when submitting events?

Hi, I was able to get the HEC up and running on a HFW, but now when I submit an event, I get "token is required", even though I'm passing a token. curl -k https://myserver.com:8088/services/collector/event -H "Authorization Splunk: 7E36213E-03E1-4246-93B9-81931D303A58" -d '{"event": "hello world"}' Anyone run into this?