Exchange Problems

[melbert2002]

I am having a problem with my exchange box. I have people who have laptops and work from home. While they are at home and they send mail addresses, they can send messages to some people, but not to others.

I.E. They can send to Yahoo addresses and our internal addresses but not to others.

When they are here in the office, they can send just fine. We are using POP3 and even when they are here in the office, they are grabbing their mail via the internet, so the situation is the same whether they are here in the office or at home. The only difference is the Internet Provider. Here is the exact message that they are getting (e-mail address has been changed):

'USER@ISP.com' on 1/13/2005 8:34 PM

550 5.7.1 Unable to relay for USER@ISP.com

Thanks for any help

 

[Marcs41]

Unable to relay is the culprit.
It just means that ISP will not allow the user to use their server to send mail from their server.
Most probable the SMTP settings in Outlook are set to use the 'wrong' ISP.

What I fail to see in your description is where exactly the Exchange Server fits in.

Marc
[sub]If 'something' 'somewhere' gives 'some' error, expect random guesses or no replies at all.
Free Tip: The F1 Key does NOT destroy your PC![/sub]
Have a look at the shop @

http://www.cafepress.com/tektips

!

 

[melbert2002]

I thought about that, and it was true for one user. They called their ISP and opened up the port to allow the smtp traffic through. He is pretty much fine now. But what is going on with one of my users who is able to send to internal e-mail addresses and yahoo addresses?

Thanks
Mel

 

[dgallegos]

You also may want to check and see if your on any black lists

 

[msbald]

Also check for multiple accounts in the outlook client. See if their "clean sends" (a new mail initiated to person x) work but replies to that same person do not then outlook is selecting the wrong account to use for sending. If only one account, are the remote users using your smtp server or their isp's. I would guess, if they have no probs in the office but are having probs in the "outside" you are
1: using your office's isp's smtp server in their pop client setup so that when the gerbils go out and connect to aol or some other isp the ISP rejects the mail. Try configuring your exchange server's smtp connector as the laptop's smtp server (of course it must be accessible from the outside on port 25 through your firewall). I tried training people to switch themselves and it was like teaching addition to a gerbil. This will work most everywhere but some ISP's block port 25 (smtp) to all but traffic headed for their own servers. A more advanced but universal configuration would be to use and additional smtp connector on a non standard port (I have never done this config

or 2. you are using the office smtp server but the exchange server just forwards this to your office isp's smtp server and your smtp server is unavailable to outside access (ie no port forward to its IP address on port 25 through the firewall / router)

hope this helps.

 

[melbert2002]

Yes, I tried that changing the SMTP server and it still is not working. I really dont know what else to do about this issue. Right now they are going to use OWA but for a machine that is their primary machine, this is not a very good answer.

Any other Ideas????

What about begging and pleading with the ISP to open it up for me?

 

[Marcs41]

Sorry, but this is not an Exchange issue at all.

Those users are using POP3 even at the office, directly to the ISP. Then they move from ISP to ISP and you expect it to keep working just like that? Every ISP has their settings, some are more flexible than others, you will need to take that in account.

There is an Exchange server, but if those users do not use it, you have no control over it, and it is not an Exchange issue.

Marc
[sub]If 'something' 'somewhere' gives 'some' error, expect random guesses or no replies at all.
Free Tip: The F1 Key does NOT destroy your PC![/sub]
Have a look at the shop @

http://www.cafepress.com/tektips

!

 

[dennisbbb]

Your Virtual SMTP server is set up to "allow relay for these subnet" and it includes your local subnet. When your users are at home, your Vitual SMTP server will simply reject them, since they are not on the "allow relay" list.

Solution:

1) input their isp subnet or

2) allow users to relay after successful authentication

 

[dennisbbb]

BTW, yahoo.com is apparently one of the domain our server is set to relay, regardless of authentication and subnet.

Also, the user who called his ISP, he is fine because he has a check on "my server requires authentication" on his client, which your server is already set up to do. (I believe this is your fix)

 

[melbert2002]

Cool deal.

Thanks for all the cool info. I am going to try and change the settings in outlook and see if authenticating will work.

Thanks again.

Mel

 

[melbert2002]

Thanks for all the help everyone. THey are working fine now.