Exchange 2003 and pop3 access

By vlazzare ·
I administer an SBS 2003 SP2 Exchange server for a client. I have set up 3rd party spam filtering. They use a Sonicwall firewall and would like to block all IPs to port 25 except a range provided by the 3rd party. I have done this, the problem is that the client has several employees that use outlook and outlook express pop mail from home and it gets blocked. As much as I'd like them to switch to OWA they won't do it. I can't open the firewall to their IPs to allow their email from home as they are not static and it'd be an administrative nightmare. Is there a way to use a different public IP at the client site to accept port 25 from these clients and then connect that to the exchange server? Or what about using port 456 on pop clients rather than port 25? Can either of these be done? Is there an easier way to set this up? Thanks for any help.

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Outlook & Exchange Setup

by chad In reply to Exchange 2003 and pop3 ac ...

Hi, this is a common scenario with mobile employees and can be easily rectified by eithe setting up Outlook with an Exchange connection, or alternative SMTP port. A question I have is in relation to POP access, if you are using Exchange, then why are some clients using POP access. If they are all setup with a current version of Outlook (not Outlook Express), then your port problem would dissapear. Simply setup the clients with Outlook, upgrade any that are on Outlook express and all will be good.

OWA is a good solution, however some may be resisting since a client on the computer is integrated with other programs, making it easy to email docs...etc. If you setup Outlook on each pc and upgrade from Outlook Express, you will get all their existing email and contacts, leading to less resistance from the users.

If you still need to have an alternative port, open up a part such as '29' on your side and update clients from '25' to '29', this will resolve port blocking. Also allowing any mobile clients to travel and remain on the original set-up. There are multiple port options, try what works best for your requirements. Hope this helps...Chad

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by cmoreland In reply to Outlook & Exchange Setup

If you're wondering how to set up their Outlook client to Exchange there is an option when configuring the account under advanced - Connection called Connect to Exchange over HTTP. You then enter your internet facing Exchange URL and they can connect over port 80 to your Exchange server.

Make sure your SSL is valid though and Outlook Anywhere is enabled on your server. I believe this will only work with Outlook 2003 or 2007 though. If they are only able to run Outlook Express you may be stuck with POP3.

You might also try having your 3rd party firewall admin set up a NAT to move only email traffic over port 25 directly to your Exchange server and 587 for outbound sending. This way you don't need another IP specifically for email.

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Alternate access to exchange

by vlazzare In reply to Outlook & Exchange Setup

Thanks to all for the quick replies. The users are both local and in Texas. All Texas people use OE. If I change the Outlook and Outlook Express clients SMTP ports to another number, is it just a matter of allowing that port through the firewall and directing it to the Exchange server? I assumed something would have to be configured on the server, but maybe I'm over thinking the issue.

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by cmoreland In reply to Alternate access to excha ...

You'll have to make sure your receive connectors on the server are configured correctly if you decide to change the port settings.

Again though, if you just set up a NAT to funnel all smtp/pop traffic through one IP I don't see how that would be a problem. I don't know about the 3rd party IP range but I suppose they could configure it that way as well. So long as people know what ip address to point their pop/smtp settings to.

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Accessing personal e-mail accounts from work...

by impact In reply to Exchange 2003 and pop3 ac ...

Well to tell you the truth most companies that are seriouse about protecting there Data & there network block access to personal e-mail, chat rooms, text messengers, Ebay etc.. Another added benefit to blocking these things is added production. If the Boss has to have it you could suggest that they be allowed to check personal e-mail on there IP's server,similar too the e-mail access on the Time Warner Roadrunner web site.

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Exchange 2003 and pop3 access

by amen In reply to Exchange 2003 and pop3 ac ...

move all users to MS OUTLOOK and use RPC over internet. You can also setup a customized port on the firewall that maps to 25 on the internal ( mail server) this way all clients are configured to connect to the new port settings.

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Updated scenario

by vlazzare In reply to Exchange 2003 and pop3 ac ...

I was away from this issue for a while but am now returning to it and wanted to update. Please see previous posts for original issue. The Sonicwall will only allow One to One NAT to a different IP in the LAN. Therefore I can route POP user SMTP to a backup 2003 DC on the LAN. Is there a way to relay this to the Exchange server? If so can anyone point me to an article that lists the steps?

Thanks for any ideas

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