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Using POP3 in conjusction with Exchange

Hi, Experts;

I have a scenario in front of me for which I need some advice.

Here’s the infrastructure setup:

SBS 2003 Standard

Everything is pretty plain Vanilla in this environment EXCEPT that rather than have the exchange server handle all incoming and outgoing email, we have an outside POP3 server provided by our Web Hosting Company for INCOMING mail. (Again, I inherited this environment….I intend to bring it all in-house in January). All of our incoming mail is delivered, of course, through the POP3 server. We have about 20-25 users.

Let’s say that the company is called

In addition to the full-time employees, the Client employs a number of independent contractors (ICs) that work from their homes…..they do not come into the office, therefore they do not need an account on our network. The Client wants them, however, to have a email address to use when they correspond with my Clients’ clients.

For instance, Kelly is an IC, so my client wants her to have the email address of

Now, this would appear to be a fairly simple task:  We simply setup a POP3 account for the IC on our Web Host’s POP3 server the same way we do for employees. The IC sets up Outlook at home using our POP3 mailserver (, and uses their own ISP for outgoing SMTP.

I have already set this up for an IC, and it appears to work very well. I have sent mail TO the IC from my home account, from the Client’s Network to the IC, I’ve done replies, added attachments, most everything I could to simulate a production environment. It all APPEARS to work FINE.

Here’s the problem:   the Client doesn’t think it will work in the long run. According to the Client, My predecessor tried setting up the same thing a couple of years ago on the same network, and while it worked part of the time, the Client said that emails began to disappear, so they changed to using Hotmail for all IC accounts. The Client contacted my Predecessor this morning to verify this, and he states that there was indeed a problem. He said that “unless JOEBLOW hosts their own mail, if an IC sends a piece of mail it never leaves the organization unless they log onto our server to use the mail (which we didn’t want to do).”

I know, that doesn’t make a whole lot of sense, but that was his email reply.

Therefore, my question to all of you is:  Is there anything here I’m missing?  Can anyone here think of a scenario where emails would be missing in a configuration like this?
I’m having a problem convincing the Client to go forward with this arrangement, because the former IT Consultant is adamant about it not being a functional solution.

Help me out!

Avatar of Mixmangle

Are you sure Exchange is not installed and running at all? THis is key, here. If it's installed, or partially installed but not configured correctly, you will have problems.

Do All Client computers use an outlook pst file and connect directly to web host's pop3 server?  If that's the case, then yes, you can set up both your "internal" and external mail at the ISP mailhost. I put internal in quotes because even internal mail between folks in the office will go out to the Internet and back.

But make sure Exchange is not installed. And when you bring it all inhouse later, make doubly sure you are aware of how to transition mail. It almost sounds like the former IT guy knows something you don't about the Exchange situation. Maybe it is set ip but not configured correctly?

Anyway. If you're sure Exchange is not installed, and everyone connects via POP3 to the external mail server, both employees and ICs, there should be no problem.
Avatar of Jeffrey Kane - TechSoEasy
It is a fairly simple task... please see my response to this Q for your how-to:  http:Q_21877908.html

Avatar of Headhunting55


Mixmangle, the exchange server IS installed and functioning. All Internal users connect to the POP3 server for their incoming mail. The outgoing mail is directed out via the exchange server.

The system I described is installed and has tested fine, but the client is concerned about problems down the road. My thought is that either it works or it doesn''s working in tests, but the real question, I suppose, is there anything anyone can see in this scenario that would an INTERMITTENCY in mail delivery?, becuase that's what I am told happened last time.

Hi, jeff...I KNEW I'd see you on this one. LOL!

Your solution looks good, I'll probably implement that.

However, for the sake of argument, (and education on my part), do YOU see anything in this setup as, I now have it, that would create a problem down the road?  It appears to work in tests.
You need to configure the setting I suggested.  If there are emails disappearing then I would suspect that the IC is using both Outlook AND Webmail.  I would also suggest that you use a General Delivery Catch-all for your email addresses that are in the office.  Because otherwise you have the POP3 connector checking 25 separate mailboxes to download messages... this can take longer than 15 minutes at times and will trample on the next task...this too will cause emails to disappear.

Honestly... with that many users you should not be using POP3 email in the office.  Instead, configure you Exchange server as it was designed... to handle SMTP mail, and then let your IC's still use POP3 from the ISP webmail server.  The POP3 connector is included with SBS really only as a bridge to help companies switch to real email.

You'll find the how-to here:
and in order to share the SMTP space with your ISP Web Server you need to follow this KB article:

All in all it's a bit of work but not rocket science... it's done by folks every day and you'll be much happier with that configuration when you're done.


Incidently, I just checked and we are NOT using the POP3 shows the service as not running. Each user has POP3 account added to their Outlook accounts in addition to the exchange server.  

I'm in agreement that we need to bring the whole mail service in-house.

Yikes... that's a total mess... what a drain on your network resources!!! When a user sends a message to the person at the desk next to them... it's quite possible that it will go out to the Internet and come back in... depeinding on what account they have set as their default in Outlook.

No wonder messages go missing!


Yes, a mess it is!

I plan to switch it over between Christmas and new years when the Company will be closed.  This client is Hypersensitive to ANY downtime.

Of course, you have all of the points on this one, and you can have my firstborn as well.....

Before I close it, though, any other comments on the scenario as presented?  Think it's work until christmas?  LOL!

Hmmm... how much do you think I can get for your firstborn.?

And if anyone reads this and complains... just remember I wasn't the one that gave the firstborn up... I just sold it.

As for working until Christmas?  I'm surprised it's still working from yesterday.  Consider 25 POP3 clients accessing messages over the same DSL line simultaneously... traffic nightmare.  You really might want to consider configuring the POP3 connector with a Catch-All acocunt at the ISP.  This will at least get you to be able to manage things centrally.  But be sure to get rid of the local POP3 accounts in Outlook... I've definitely seen that to be a case of missing emails as well.

There's little risk of downtime in making that change since the messages will all sit at the ISP during the configuration.  

After giving this some thought, I'm going to backtrack here a bit, because although I have gotten some EXCELLENT advice from jeff (as usual), I'm not sure I actually have my question answered. I'm not all that sure I was really clear in my question.

Even though the Client's system is a bit convoluted using the Webhosts POP3 server for incoming mail, we have not experienced any real email loss while I have been with this client. The email loss that is stated to have occurred was in the PAST, when the method I am suggesting was implemented by the previous consultant. When I implemented this method and tested it, it appeared to work fine. I suppose I am looking for a concept or theory stating that "yes, this method SHOULD work if everything else in the Exchange Server is functioning correctly, or NO, it will NOT work, or Will work intermittently, and here is the reason why."

From what I am gathering, the previous consultant is suggesting that while EXTERNALLY there should should be no problem with an IC communicating with outside clients and vendors, it's the INTERNAL communication to the OUTSIDE IC that seems to be the problem. For instance, if (internal) sends an email to (EXTERNAL IC with an account on our Webhosts POP3 server that hosts our domain and processes our POP3 email, but does NOT have an account on our Internal SBS Exchange server), is there something in this transaction that may cause the email to disappear?

I think the theory MAY be that if (internal) sends an email to that if Exchange sees an email going to the SAME domain, it may look for an account for kelly internally, and if doesn't see it, it may dump the email. SO FAR, in my tests, that has not occurred....I just need to know if there is validity to this idea.

Jeff, I'm gonna bump this up to 500 points, and not only can you have my firstborn, but you can have my Mother-in-Law as well.

Avatar of Jeffrey Kane - TechSoEasy
Jeffrey Kane - TechSoEasy
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Jeff, as usual, you da man.  I have decided to keep my Firstborn....he's a great fishing buddy....., however i will be sending along my mother in law to you shortly.