[Resolved] What does "550 Too many invalid recipients" mean?

Author	All Replies
Mango www.toao.net join:2008-12-25 Alberta kudos:11 Reviews: ·Anveo ·Shaw ·AcroVoice ·Callcentric ·callwithus ·voip.ms ·FreePhoneLine ·TELUS 2 edits	[Resolved] What does "550 Too many invalid recipients" mean? ...besides the obvious? We were receiving the following error when our corporate mail server tried to send mail to any @shaw.ca address. SMTP error from remote mail server after initial connection: host idcmail.shaw.ca [64.59.134.8]: 550 Too many invalid recipients We checked the usual suspects - made sure we were not accidentally on any black list, checked to see if we had done any mass mailings recently (we hadn't) and triple-checked the spelling of the addresses we were sending to. Hotmail and Gmail -> Shaw worked. Corporate mail server -> Hotmail and Gmail worked. The problem went away while I was on hold with Shaw so we didn't get a chance to properly troubleshoot it. If anyone has some suggestions for what I should do next time, I would appreciate it. Thanks, Mango
	to forum · permalink · 2012-12-07 11:01:34 ·
Shaw_Alex Official Shaw Rep join:2010-12-16 kudos:1	Re: What does "550 Too many invalid recipients" mean? Hey Mango, Send me a message with your account number and i'll look into it. I'm not an expert with email related issues, but I can pass it on to one of my contacts -Alex
	to forum · permalink · 2012-12-07 12:07:08 ·

Mango www.toao.net join:2008-12-25 Alberta kudos:11	reply to Shaw_Alex Re: What does "550 Too many invalid recipients" mean? Thank you.
	to forum · permalink · 2012-12-07 12:15:24 ·
Mango www.toao.net join:2008-12-25 Alberta kudos:11 Reviews: ·Anveo ·Shaw ·AcroVoice ·Callcentric ·callwithus ·voip.ms ·FreePhoneLine ·TELUS	The verdict: I'm guilty. We have phone service with Shaw and our system was accidentally configured to send an autoresponse every time Shaw sent us an email with our voicemail. I corrected this and the problem seems to be resolved. Thanks to Alex and Nathan for helping me track it down! m. -- Dear Obihai, please fix the FXS to FXO Relay in the OBi110. Add this as your signature if you agree!
	to forum · permalink · 2012-12-07 15:14:03 ·
8744675 join:2000-10-10 Decatur, GA	reply to Mango Some mail servers will temporarily black list a mail server's IP address if it send too many successive e-mails to unknown addresses in that domain. It's a way to prevent dictionary attacks where they keep hitting the mail server with different e-mail prefixes at that domain until one matches a real user. It tries every word in the dictionary until it gets a hit. It's a way for spammers to validate or harvest e-mail addresses for spam lists or to hack an account. Somehow it thinks your e-mail server is messing with theirs.
	to forum · permalink · 2012-12-07 15:24:48 ·

O Canada! > Canadian > Shaw > [Resolved] What does "550 Too many invalid recipients" mean?

Re: What does "550 Too many invalid recipients" mean?

Re: What does "550 Too many invalid recipients" mean?