MikefromMB
IS-IT--Management
Hello IT People,
So I have one person in my staff I support who keeps getting some of his outgoing messages denied, returned to him with the following error:
Server error: '550 5.7.1 <intended recipient>... Relaying denied: You must check for new mail before sending mail. [IP ADDR]'
I know that this message related to POP-before-SMTP authentication, which we all have set-up by default. I have checked his settings multiple times and he does, indeed, have the right authentication settings. So what I find weird is that he gets this error even when I know for a fact that he has the right SMTP authentication settings. I'm stumped as to why this would occur for only him.
Here are some notes:
- His e-mail client is Outlook 2013. His settings are proper in that he has the right port number (587) with security setting (TLS) and it's set to authenticate with the POP before sending ("log on to incoming mail server before sending").
- He does sent lots of little e-mails throughout the day; it's almost like instant messaging to him. I have verified and while he does send a lot of messages, it's no where near the limits set by the server.
- The issue only seems to occur in the afternoon (after many messages are sent).
- Our e-mail servers are hosted by our service provider.
- He works at a remote location where his Internet connection is provided by radio waves. He does have a static IP for his location. There are 3 others who work with him and no one else is reporting this problem (but they're averaging 1-2 messages sent a day; no where near what he sends).
- I've checked with his ISP and they've assured me that they let all standard POP, IMAP and SMTP ports through w/o any interference. (Making sure it's not his ISP in any way)
- I've rebuilt his entire MAPI profile in Outlook and it still occurs.
- I'm trying another e-mail client but right now my tests are inconclusive since I have not have enough time to really test thoroughly.
I guess my first question is this:
Does anyone know how the POP-before-SMTP, or more specifically the "Log on to incoming mail server before sending" in Outlook actually work? Could it be an issue of timing? For example, could it be that the "Log on" part is only done every x minutes rather than every time one hits 'Send', meaning it assumes that since it checked for mail, say, 1 minute ago, it does not actually log on to POP before sending every time?
This is my hypothesis for now: that his instant-messaging style of communication (many little messages send back-and-forth in a short time span) coupled with the fact that Outlook really only logs on every x minutes rather than every time (I speculate) might explain why he gets the "Relaying Denied" messages when, in fact, the settings are proper.
I submit this to you, fellow techs, to know what you think.
Thanks.
So I have one person in my staff I support who keeps getting some of his outgoing messages denied, returned to him with the following error:
Server error: '550 5.7.1 <intended recipient>... Relaying denied: You must check for new mail before sending mail. [IP ADDR]'
I know that this message related to POP-before-SMTP authentication, which we all have set-up by default. I have checked his settings multiple times and he does, indeed, have the right authentication settings. So what I find weird is that he gets this error even when I know for a fact that he has the right SMTP authentication settings. I'm stumped as to why this would occur for only him.
Here are some notes:
- His e-mail client is Outlook 2013. His settings are proper in that he has the right port number (587) with security setting (TLS) and it's set to authenticate with the POP before sending ("log on to incoming mail server before sending").
- He does sent lots of little e-mails throughout the day; it's almost like instant messaging to him. I have verified and while he does send a lot of messages, it's no where near the limits set by the server.
- The issue only seems to occur in the afternoon (after many messages are sent).
- Our e-mail servers are hosted by our service provider.
- He works at a remote location where his Internet connection is provided by radio waves. He does have a static IP for his location. There are 3 others who work with him and no one else is reporting this problem (but they're averaging 1-2 messages sent a day; no where near what he sends).
- I've checked with his ISP and they've assured me that they let all standard POP, IMAP and SMTP ports through w/o any interference. (Making sure it's not his ISP in any way)
- I've rebuilt his entire MAPI profile in Outlook and it still occurs.
- I'm trying another e-mail client but right now my tests are inconclusive since I have not have enough time to really test thoroughly.
I guess my first question is this:
Does anyone know how the POP-before-SMTP, or more specifically the "Log on to incoming mail server before sending" in Outlook actually work? Could it be an issue of timing? For example, could it be that the "Log on" part is only done every x minutes rather than every time one hits 'Send', meaning it assumes that since it checked for mail, say, 1 minute ago, it does not actually log on to POP before sending every time?
This is my hypothesis for now: that his instant-messaging style of communication (many little messages send back-and-forth in a short time span) coupled with the fact that Outlook really only logs on every x minutes rather than every time (I speculate) might explain why he gets the "Relaying Denied" messages when, in fact, the settings are proper.
I submit this to you, fellow techs, to know what you think.
Thanks.