Exchange 2003 server stopped providing POP3 server

I have been running Exchange 2003 and have the POP3 virtual server enabled. This has been working fine, allowing me to retrive my Exchange email using POP3 when offsite.

This suddenly stopped working and although Outlook 2003 now reports success sending POP3 via my Exchange server (i.e. by the SMTP virtual server), it reports the ubiquitous "800ccc0f" errro on receiving (server terminated the connection).

I can see no reason why it would start doing this.
One thing has changed on the server - I have just set up a VPN and hence changed remote access policies to the server itself (because this is SBS 2003 and the server runs all of the BackOffice).
However this was only to allow VPN ports to open and connections to be made. This should affect Exchange so I think it's coincidence.

Any thoughts out there?

Nick

 

Whoops - I meant this "should NOT" affect Exchange.

 

Some VPN clients will block other ports whilst a connection is in place. This is a security measure to stop someone on the internet connecting into a VPN via an unsecured client. I don't know if this is also the case with the 2003 VPN system, but it would account for the coincidence of setting up VPN and closing of ports.

Something to check: the POP3 service uses port 110 at the server end. Try telneting into port 110 on the server. You should get a connection. Try connecting from the LAN side and the internet side. The results of this test should point you in the right direction.

If you can connect from the LAN side, that suggests Exchange is working properly. Try using a POP3 client (Outlook, Outlook Express, Thunderbird, or Pegasus for example) to connect to the server from the LAN side. If you can, Exchange is working fine. The problem is with your WAN setup. Try uninstalling the VPN and try again. Also check your ISA set up - you need to allow incoming port 110 through the firewall.

If you can't get a connection to port 110 at all, the POP3 service on the server isn't working.

If you can telnet port 110 from both inside and outside your network, then you've got a configuration problem. I'd start by trying a different client. I've found instances where Outlook Express gives more useful error messages than Outlook. Try a couple of other e-mail client software packages. One might give you just the bit of information in the error message, that will tell you what is wrong.

 

Interesting Reggie.
I can telnet both internal and external.
And using OE6, it connects and downloads the messages.
Outlook doesn't though. Any more ideas?

Nick

 

Further info:
Just tried the "Test Settings" in Outlook 2003.

The error says:
"Log onto incoming mail server (POP3): The specified server was found but there was no response from the server. Please verify that the port and SSL information is correct. To access these settings close this dialog, then click More Settings and click on the Advanced tab. "

Of course, the settings are the same as in OE6, which works.

 

Unfortunately I use neither Outlook 2003 nor the latest version of Exchange. I'd expect it is a permissions problem. In Outlook 2000 I'd be looking in the Services properties for authentication options.

Sorry I can't help more.

 

Hmmm, I'm not using SPA, just clear password for the purposes of this test.
Just tried firing up the laptop while on the wireless LAN near the server.
I'm logged on locally, not on the domain, and still Outlook connects immediately and downloads the messages.

Do it out of office over the internet and the connection is refused. And yet Outlook Express works perfectly with the same settings.

Confusing or what?

 

How about trying Thunderbird - another POP3 client - just to see how that manages. As I said in an earlier post - it might just pop up an error message that gives you a better idea of what the problem is.

http://www.mozilla.org/products/thunderbird/

 

Just like Outlook Express, Thunderbird works fine.
This looks, therefore, like an Outlook 2003 issue. Odd because SBS 2003 gives you Outlook 2003 as the preferred client that has all the functionality to support W2k3 and Exchange 2003.

Anyone got any ideas how to troubleshoot this? I'd prefer to stick with one client and Outlook 2003 is the one designed for this - plus all my mail, contacts, calendar etc are already in Outlook.

 

Well here's something bizarre. May be a red herring but if I check email with Thunderbird before starting up Outlook , then it seems outlook will download the data. This has worked twice now.

If I open Thundernbird and check email, when Outlook was already open, Outlook still can't get mail.

This is so odd it has to be just coincidence, surely.

 

That is bizarre. However, if I assume it isn't just a coincidence there are a couple of things that can be deduce I think.

1. I don't think this is a firewall/ISA problem. The client side port address will be different for each application. That means a firewall at the server end would see the traffic from Thunderbird as a different session to that from Outlook. So it is unlikely that Outlook is hijacking a connection opened up by Thunderbird.

2. I doubt it is an Exchange problem. Communication with the e-mail system will be POP3 and those protocols shouldn't be too different between different client software applications.

I wonder if the problem is name resolution within Outlook. That would account for the behaviour you are seeing. If you have Outlook set up to connect to the e-mail server by name, it may be having problems resolving the server's IP address to that name. Thunderbird is not suffering from the same problem (perhaps because you've only used it from outside the network and therefore it has only had one address bound to the server name) and is able to resolve the server name to an IP address and connect. Once the name resolution has occured it will be in the local cache for a short while. If Outlook tries to connect while the resolution is still in cache, it may well be able to use the cached information to connect.

So a solution : if I am right, you could try changing the server settings in Outlook, from the server's name, to its external IP address.

This may end up being a little clunky as you'll need to change the address when you are inside your network. I'd suggest creating two connections: an internal one and an external one.

 

Tried again. Outlook was giving the error. I started Thunderbird and did a connect with that, then did a Send/Receive with Outlook. Worked successfully.

Next, killed the dial up from my laptop, killed Outlook and re-dialled. It was successful, without Thunderbird running.
Flushed the DNS cache using IPCONFIG /FLUSHDNS and it's still working. So it doesn't look like name resolution from that perspective. On the other hand the full email domain name doesn't appear in the DNS cache using ipconfig /displaydns, only the actual server name.
Does Outlook use another mechanism than DNS to find the host?

I need to use a hostname not an IP address, because until BT can provide me broadband and therefore a fixed IP, I have to use Dynamic DNS to keep the IP address up-to-date in the DNS system. So using a number for IP is not an option

At the moment it's working but I suspect not for long....

 

Outlook should use DNS to resolve fully qualified domain names (for example Myserve.mydomain.com), but may not use it to resolve NetBIOS names (for example Myserver). In NT4 days I was sure about the cut off. With active directory and Win2000, name resolution isn't so clearly defined (to me anyway). However, 2000 systems and beyond work best if you specify either IP address or fully qualified domain names (which means you have to have DNS set up correctly). When using fully qualified domain names application should use DNS. However, it would surprise me if Outlook had it's own cache.

So a lot of waffle from me. In short, I'm out of suggestions.

I can sympathise with you over the BT broadband issue. I work in the back end of Herefordshire and BT broadband isn't coming until spring next year at the least. We have a satellite broadband connection, which is OK. However, my internet access at home (where I do have broadband) is so much better. I can't wait until it findly rolls out to us.

How are you connecting? Via dialup? if so there are UK ISPs that will provide you with a static IP with a business dialup solution.

 

Hi Reggie

Just for the moment Outlook is working - with absolutely no change to my system.
I wasn't aware there were ISPs who would provide static IP for dial-up. I'll do a search on that!

At the moment BT just says "no, you're out of range" whenever I apply to an ISP for broadband. This is irritatingg because for a while they had a policy of sending someone out to test line noise/loss for any application made. In my new house I may have a good enough quality line, but they won't test it!

Ah well....

 

Nick,

Here is an example of a UK ISP who will do static IP on dial-up: Plus net. Their broadband solutions are good and very competetive too. That'll give you a start. There are a number of other too, so worth a hunt round for a deal that suits you.

 

Very manythanks Reggie.

BT seems to have cottoned on to the fact that it has lots of users who may be prepared to accept slower ADSL than 2Mbit, in order to get an improvement over dial-up, and always-on connection.

My latest check showed that they are now prepared to come and measure line noise again and may be prepared to give me a broadband connection albeit only at 256 or 512. Well that's significantly better than 45k!!

Whether they'll say yes after the line check is another questionm, but here's hoping.

In desperation, I found an MS article that said failure to get a server response could be due to damaged Outlook profile and try creating another.
This I did, and immediately connected and started to download my inbox. Not as good a housekeeper as I should be so there are 130 emails in there, but it seems to be working.
Then I'll need to import all the existing contacts and calendar from my local PST file, and hook up the other PDSTs I use to keep the main inbox PST below 300Mb!

If it still downloads reliably after that, I can disconnect the old personal folder, delete the old profile, rename the new profile and I should be in business.

What it is that gets damaged, MS don't say.
Have I got resolution of the problem? Only time and experience will tell.


Nick

 

Nick,

I'm glad you seem to have a solution. Any chance of posting the Microsoft article number (usually starts with a Q) so others can get to it, if they have a similar problem?

It is not just speed that makes ADSL worthwhile. The always on facility is greatly enabling. Even simple things like AntiVirus updating become so much easier.

All the best

Reggie

 

Aaaarrrgh.
As expected, it didn't last long. All day yesterday, but this morning not working again.
So much for Microsoft's premier email client. Maybe I'll try reinstalling Outlook 2000 - perhaps it's just the new version.

 

The MS article is Q813514

All is now working for me. I finally got broadband and ditched the USB modem they supplied in favour of an ethernet DSL modem. I cannow get all my POP mail from the server.

I have a different problem now, but that's subject for another post....