Don't know what section this should go, but in any case.
Our business moved over to a new ISP (ADSL and hosting) at the beginning of this month. Everything is going smoothly but we can't seem to email out to a few clients (90% are working) and get an Undelivered Mail Returned to Sender error back. Also included is this link, something about openspf.
The ISP is looking into it, but it is getting really annoying right about now as we can't contact some clients. It only happened when we moved over to the new ISP.
By checking that error message, does anyone have any ideas - I don't have know enough to figure this one out. I have changed ports and outgoing mail servers as much as I can. Seems like they are cybersmart resellers, but smtp.cybersmart.co.za doesn't work.
1 <1 ms <1 ms <1 ms 192.168.0.1
2 1 ms <1 ms <1 ms 192.168.100.1
3 60 ms 59 ms 60 ms 184.108.40.206-discover.co.za [220.127.116.11]
4 34 ms 36 ms 36 ms ct1-ipc-up.cybersmart.co.za [18.104.22.168]
5 13 ms 13 ms 13 ms google.cinx.net.za [22.214.171.124]
6 52 ms 49 ms 45 ms 126.96.36.199
7 112 ms * 66 ms cpt01s01-in-f16.1e100.net [188.8.131.52]