IMAP4+ISA+Cellphones=inbound fine, outbound no go

We have a few users that have cell phones in Europe like the nokia 9100 that can send/receive via pop3 or IMAP4.

I have setup Exchange and ISA to allow IMAP, and they can sync their mail just fine.  But they cannot send email out via that account through their phones.

Their IMAP settings are:

inbound server - mail.domain.com
outbound server - mail.domain.com
SMTP server requires authentication = YES
username, password, etc.

Any ideas on why outbound wouldn't work?  Is it possible that it works similar to home ISP's in that you have to use their outbound mail servers?  That's about the only thing I can think of at this point.
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TheCleanerAsked:
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LeeDerbyshireCommented:
Have you configured the SMTP server so that Authenticated Users can relay through it (Access Tab, Relay button)?  Or is that what you meant where you said 'SMTP server requires authentication'.
TheCleanerAuthor Commented:
Well, the "allow all computers that succesfully authenticate regardless of the list above" is checked.

The SMTP server requires authentication = YES is on the phone part.


They "can" send email to other users on our domain.
LeeDerbyshireCommented:
Oh, right - I see now.  Do you have SMTP logging turned on (Default SMTP Virtual Server/General tab)?  If not, I would enable it for a short while as you try to send a message through the server.  Open the log in Notepad after the attempt, and see what was written to it, if anything.
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TheCleanerAuthor Commented:
Did that but don't know what I'm looking at now:

#Software: Microsoft Internet Information Services 6.0
#Version: 1.0
#Date: 2006-02-10 20:12:18
#Fields: time c-ip cs-method cs-uri-stem sc-status
20:12:18 4.79.181.14 - - 0
20:12:18 4.79.181.14 QUIT - 0
20:12:18 4.79.181.14 - - 0
#Software: Microsoft Internet Information Services 6.0
#Version: 1.0
#Date: 2006-02-10 20:12:27
#Fields: time c-ip cs-method cs-uri-stem sc-status
20:12:27 10.10.10.250 EHLO - 250
20:12:27 10.10.10.250 MAIL - 250
20:12:27 10.10.10.250 RCPT - 250
20:12:27 10.10.10.250 DATA - 250
20:12:27 10.10.10.250 QUIT - 240
20:12:50 10.10.10.5 HELO - 250
20:12:50 10.10.10.5 MAIL - 250
20:12:50 10.10.10.5 RCPT - 250
20:12:50 10.10.10.5 DATA - 250
20:12:50 10.10.10.5 QUIT - 240
20:12:50 10.10.10.5 HELO - 250
20:12:50 10.10.10.5 MAIL - 250
20:12:50 10.10.10.5 RCPT - 250
20:12:50 10.10.10.5 DATA - 250
20:12:50 10.10.10.5 QUIT - 240




The phone also says "Message sending failed, check your settings"  which isn't much help.
TheCleanerAuthor Commented:
I should mention that the bottom with 10.10.10.250 and 10.10.10.5 is not the problem phone.  Those are internal AS/400 servers sending mail.
LeeDerbyshireCommented:
Can you try to send a message from the phone, and see if anything is written when you make the attempt?  If nothing is written, then it's not even reaching the server.  The leftmost column is the time.
TheCleanerAuthor Commented:
Yeah, nothing is written, unless that 4.79.181.4 is it.
LeeDerbyshireCommented:
Go to http://www.samspade.org/t/ipwhois?a=4.79.181.4 .  It says that IP address belongs to Level 3.  Is that who your users connect to?
TheCleanerAuthor Commented:
I don't know, other than it is a T-Mobile account for his phone.

If I got to www.whatismyip.com on his phone I get:

166.220.59.96

I know that doesn't help you to answer this... :)

I did find this... http://www.howardforums.com/archive/topic/833144-1.html

so I'm curious if maybe they have to go outbound SMTP through Tmobile?
LeeDerbyshireCommented:
Well, it looks like the phone isn't connecting to your server, then.  I think you need to ask T-mobile if you are allowed to direct SMTP clients to your own server.  It may be against their terms of service.
LimeSMJCommented:
My mobile users have T-Mobile air cards and within the past year they have restricted the use of port 25 in my area.  

In turn, I have created a new Virtual SMTP server exclusively for my air card users... Leaving the POP3 settings alone, I changed the authenticated SMTP port from the default 25 to another port (use anything > 1024) and everything works fine.  Just make sure you create an inbound listener for ISA to look at the new port you are using.

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LimeSMJCommented:
Oh and changing the SMTP server on the mobile phone to T-Mobile's server will also bounce emails because they have a restriction (in my areas of use) that the reply address have a T-Mobile email address... which was another motivating factor to create the new authenticating SMTP relay on our end since having different reply addresses was not an option.
TheCleanerAuthor Commented:
Well, no real solution was found....I told him he was out of luck and to get a cell phone that supported activesync like the rest of the company ... :)

Thanks all.
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