Horde error (RELAY LOCK)

[DCNet_James]

Anytime someone tries to send email via Horde to an external address they get the following error:
Error There was an error sending your message: unable to add recipient [[email protected]]: Invalid response code received from server

Which generates the following in the maillog:
May 30 18:12:42 cartman imapd: Connection, ip=[127.0.0.1]
May 30 18:12:42 cartman imapd: IMAP connect from @ [127.0.0.1]INFO: LOGIN, user=james, ip=[127.0.0.1], protocol=IMAP
May 30 18:12:42 cartman relaylock: /usr/local/psa/qmail/bin/relaylock: mail from 127.0.0.1:54623 (localhost)
May 30 18:12:42 cartman imapd: 1149030762.898686 LOGOUT, user=james, ip=[127.0.0.1], headers=0, body=0, rcvd=61, sent=506, maildir=/usr/local/psa/qmail/mailnames/mydomain.com/james/Maildir


Anyone have a quick answer to this before I have to start really digging?

I changed the domains on purpose so NO I didn't actually try sending to someexternaldomain.com

 

[DCNet_James]

Just an FYI to anyone who might stupidly come across this error. Previous to version 8, you did not necessarily have to whitelist 127.0.0.1/32 to use local mail relay. I had only whitelisted the real IPv4 space and not the localhost IP in 7.5.x and Horde worked w/o issues. Since 8, I've whitelisted 127.0.0.1/32 and now it works. Maybe this was always the case, but I've never had this issue until now. I've also been able to do shell side local relay w/o whitelisting. So maybe its just Horde.

Anyhow thats the fix, whitelist all of your real IP space as well as any localhost IP space.