I was able to get DEP and our on-site JSS tied together yesterday but was still having trouble getting the computers to enroll during the setup assistant. We fired up a hotspot to test DEP off our network and to our surprise it worked perfectly.
I placed a call to our firewall (fortinet) support to see if there was something I did wrong. We fired up a remote session and they confirmed we had the ports unblocked in the firewall. During several tests they noted that the firewall policy was behaving properly and that the packets were being rejected from the Mac Server (sending back an "rst" or reset packet).
Our Mac server is a Mac Mini running 10.9.5 with JSS 9.73. The firewall is off and it is on the same subnet as everything else (currently a flat open network). Am I wrong in thinking this has to be a firewall issue, regardless of what the support said, because DEP worked off our network?
Here is the error from the log if that helps at all: 9/9/15 7:27:17.557 AM apspd[165]: stream: received error: The operation couldn’t be completed. (OSStatus error -9806.) on: incoming stream: apns:com.apple.mgmt to host: gateway.push.apple.com:2195
Any suggestions are more than welcome! Thanks!