Windows, Operating System, Security, Networking, Malware, Support, Forum, Help Site Check Our Facebook Page!

Windows XP Post your Windows XP related questions here.

Register your FREE account to unlock additional features at
LinkBack Thread Tools
Old 6th November 2003   #1
Join Date: Jan 2002
Location: Sweden
Posts: 106
Computer Experience:
Laage Reputation Level

Using SMTP (port 25) on Windows XP Pro

I'm running an XP Pro (SP1 + hotfixes) box on a domain-network consisting primarily of 2K boxes and I have a mysterious problem with my machine.

Immediately after I've restarted the machine I can use Outlook to send mail (SMTP on port 25) and I can telnet to our mail server via port 25, but after a short while it seems as if port 25 is being blocked somehow, Outlook claims that it cannot connect to the server and a telnet attempt via port 25 gives this result "Connecting To [mail server]...Could not open connection to the host, on port 25: Connect failed."
The IMAP service on the mail server works flawlessly all the time and I can send mail via the web mail interface on the server (port 80).

If I go to a 2K box on the network, I have no problem telnetting to port 25 and I get the 220 ESMTP prompt just fine. So the SMTP service is running just fine on the mail server.

I've been using my machine as a local webserver for a few sites I've been working on and IIS had started the local SMTP service on the machine as well, so I stopped that service thinking that might block the port somehow, but that's not changed anything. I still cannot connect to/from port 25.

Our network is firewalled by a hardware firewall, so I'm not running any third party software firewall, and I've checked that I'd not inadvertently activated XP's own ICF.

I've tried connecting to the server using it's IP, Short network name and it's fully qualified domain name, and all of these work fine with Ping and HTTP access it's just SMTP that doesn't work.

My machine is on the same subnet as the mail server, and some of the 2K boxes I've tested with are on different subnets, and they still connect just fine.

The mail server is a Windows Server 2003 (continually updated with hotfixes) box running MDaemon (latest version), but there is no real problem there as everyone else connects just fine.

I've chosen to place this in the Win XP section rather than in the "Network" or "Other programs" section because this only seems to affect the XP machine I'm using and not any of the 2K boxes on the network, and since I can't even telnet via the port in question it doesn't seem like a specific Outlook problem either.

Any suggestions are welcomed...

Laage is offline  


to remove this ad.

Old 8th November 2003   #2
Join Date: Nov 2003
Location: Sweden
Posts: 1
Computer Experience:
Raistlin Reputation Level


Have You checked the MDaemon logs? It might give You some clue...

Raistlin is offline  

Did you find this post helpful? Yes | No



Are you having the same problem? Please post a new thread, but first you'll have to join us by Registering (FREE).

Discussion Forums
Operating Systems
Windows 10 Windows 10
Windows 8 Windows 8
Windows 7 Windows 7
Windows Vista Windows Vista
Windows XP Windows XP
Windows Server System Windows Server System
Legacy Windows OS Legacy Windows OS
Internet & Networking
Networking (Hardware & Software) Networking
Internet Explorer Internet Explorer
Microsoft Mail Microsoft Mail
Firefox, Thunderbird & SeaMonkey Firefox, Thunderbird
      & SeaMonkey

Web Applications & Cloud Web Applications & Cloud
General Internet
Malware and Virus Removal Malware and Virus

Security and Privacy Security and Privacy

Other PC Software Other PC Software
Test Posts Test Posts
PC Hardware PC Hardware
Mobile Devices Mobile Devices
Introductions Introductions
General Discussions General Discussions
Site Comments & Suggestions Site Comments
      & Suggestions

News News @ WindowsBBS

Thread Tools

Find us on Facebook   Web Of Trust Rating

All times are GMT. The time now is 05:04.

Recent Discussions
LAN disconnect for no rea.. (3)
PC Cannot Find My Printer.. (2)
MP4 to DVD (5)
New SpywareBlaster update.. (0)
ISO download (1)
Issue With My Documents F.. (5)
Security Center error (5)
Removed a network folder .. (4)
Why does Win 10 keep upda.. (3)
Browser availability in W.. (5)
Windows 10 - Sound File A.. (8)
SSD and locked rights (7)
Computer Hanging up when .. (22)
Inaccessible boot drive m.. (23)
Windows phone 8.1 Update .. (0)
The Windows Update Icon i.. (11)
Windows 95 was released 2.. (1)
Lost some of my audio, so.. (41)
[Problem opening contacts.. (5)
Would a new motherboard r.. (6)

Support Windows BBS!

Powered by vBulletin® Copyright ©2000 - 2015, Jelsoft Enterprises Ltd.
Content Relevant URLs by vBSEO
Copyright 2002 - 2015 All rights reserved.
Terms of Use, Legal Information & Privacy Policy
Page generated in 0.06445 seconds with 7 queries