Troubleshooting SMTP Send Failed

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Jeremiah Henry
Posts: 3
Joined: Thu Jun 23, 2022 1:51 am

Troubleshooting SMTP Send Failed

Post by Jeremiah Henry »

Greetings folks,

I'm trying to troubleshoot SMTP mail and "SMTP Send Failed" in my audit trail.

I'm running MBBSv10 on an Azure VM running Windows Server 2022. I've opened ports 25,465,587,2525 in the Azure network interface and in Windows Firewall. I've also allowed all traffic on Windows Firewall for C:\MBBSv10\WGSERVER.EXE, W32MKDE.EXE, AND W32MKSET.EXE.

I've tried with and without USESMRT (and in the case of USESMRT = Yes, I've verified all the SMTP server settings as accurate and otherwise functioning).

Honestly, I'm not sure exactly what ports should be open and what .exe files should be given inbound and outbound permission in Windows Firewall. I'm just shooting from the hip so far.

Any ideas?

Thanks!

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BlaZ
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Location: Peoria, IL
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Re: Troubleshooting SMTP Send Failed

Post by BlaZ »

We got this solved (at least the send portion) last night in the Teleconference. Using DNSexit as a relay host seems to have done the trick.

Jeremiah Henry
Posts: 3
Joined: Thu Jun 23, 2022 1:51 am

Re: Troubleshooting SMTP Send Failed

Post by Jeremiah Henry »

And for the sake of posterity (and everyone's sanity), I've since locked port 25 back down. I do not recommend opening that port long term. If you do, botnets will love you.

Now on to the receiving side of things, could it be as simple as a proper MX record pointing to the BBS host address?

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Duckula
Posts: 356
Joined: Wed Jul 22, 2020 1:19 am

Re: Troubleshooting SMTP Send Failed

Post by Duckula »

It could be, should be easy enough to test though.

What is happening when you try to receive?
-- Duckula

// Site admin
// Galacticomm IP owner

daniel_spain
Posts: 392
Joined: Sun Aug 09, 2020 2:39 am

Re: Troubleshooting SMTP Send Failed

Post by daniel_spain »

Jeremiah Henry wrote:
> Greetings folks,
>
> I'm trying to troubleshoot SMTP mail and "SMTP Send Failed" in my
> audit trail.
>
> I'm running MBBSv10 on an Azure VM running Windows Server 2022. I've opened
> ports 25,465,587,2525 in the Azure network interface and in Windows
> Firewall. I've also allowed all traffic on Windows Firewall for
> C:\MBBSv10\WGSERVER.EXE, W32MKDE.EXE, AND W32MKSET.EXE.
>
> I've tried with and without USESMRT (and in the case of USESMRT = Yes, I've
> verified all the SMTP server settings as accurate and otherwise
> functioning).
>
> Honestly, I'm not sure exactly what ports should be open and what .exe
> files should be given inbound and outbound permission in Windows Firewall.
> I'm just shooting from the hip so far.
>
> Any ideas?
>
> Thanks!

so one thing to remember is while the ICO addons for worldgroup used rfc standards they missed the mark on many of them. i redid the SMTP stuff back in 2013
so wg itself can deliver/receive out of the box if you are on an isp that does not restrict you to logging in (xfinity business comes to mind, as does verizon business)
but most residential accounts do not give this and you have to relay but wg has no login stuff. so i whipped up a modified smtp core that simply connects to a smarthost
logs in with a name and password, then does its thing.
this is of course if your smarthost is not requiring ssl/tls as it only uses the simple base64 encryption simple method but i did make it so you can have it on an alternate port
for relaying.... i never tested receiving on a port other than 25 but again this mod was done to fit my specific needs and it just happened to work for other sysops
as well.

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BlaZ
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Re: Troubleshooting SMTP Send Failed

Post by BlaZ »

I don't believe I ever mentioned it in here, but after BadOPCode and I assisted bbs.firewelltech.com getting SMTP Out working, I decided to try out that same method on thepenaltybox.org. I was getting an error message that there was an address syntax error. I figured out what the problem was. There is a CNF setting to append the DNS hostname to outgoing e-mails. Since my BBS has no hostname, it was attempting to send my e-mails from BlaZ@.thepenaltybox.org and the relay server was rejecting it. Fixed. :)

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Duckula
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Joined: Wed Jul 22, 2020 1:19 am

Re: Troubleshooting SMTP Send Failed

Post by Duckula »

Nice catch - thanks!
-- Duckula

// Site admin
// Galacticomm IP owner

Ragtop
Posts: 67
Joined: Sun Aug 30, 2020 11:21 pm

Re: Troubleshooting SMTP Send Failed

Post by Ragtop »

Ok this is strange. I've been fighting with this SMTP problem off and on for years with no success. Just tried dnsexit and noticed this in my audit log. With my regular smarthost (domain.com), I get this error message: (Dial) Failed to connect to 66.96.140.125

When I changed to dnsexit, I get this message: (Dial) Failed to connect to 66.96.140.125

See what the problem is? Is there somewhere else this needs to be changed that I'm just not seeing? By the way, dnsexit's IP resolves to 64.182.102.185 and domain.com is 66.96.162.96, so it's definitely getting an address from somewhere else.

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BlaZ
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Re: Troubleshooting SMTP Send Failed

Post by BlaZ »

Looks like that IP is assigned to a datacenter in Jacksonville, FL. Is that your ISP by any chance?

Ragtop
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Joined: Sun Aug 30, 2020 11:21 pm

Re: Troubleshooting SMTP Send Failed

Post by Ragtop »

Nope. I'm in Louisville. It's not changing when I change the smart host address so I'm wondering if it's pulling from a setting somewhere else or if it's hard coded in galsmtp somewhere.

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