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Email attchment problem, error 0x800CCC0F

Posted on 2007-08-01
Medium Priority
Last Modified: 2013-11-30
Im looking for help on an odd email problem. I have two computers on the same cable modem, connected to the ISP via an Ethernet hub. Both computers are on WinXP SP2, Asus K8N MoBo. One computer does the following:

When sending an email with an attachment of approximately 3.5MB or larger, Thunderbird gives me the following error:  "Sending of message failed. The message could not be sent because connecting to SMTP server smtp.central.cox.net failed. The server may be unavailable or is refusing SMTP connections." Please verify that your SMTP server setting is correct and try again, or else contact your network administrator. 

Sending the same file via Outlook Express gives me the following error:  Your server has unexpectedly terminated the connection.  Possible causes for this include server problems, network problems, or a long period of inactivity.  Account pop.central.cox.net', Server: smtp.central.cox.net', Protocol: SMPT, Port 25, Secure(SSL): No, Error Number: 

Smaller attachments and emails with no attachments go through both programs with no problems. My ISP has a limit of 10MB. The second computer handles the same attachments with no problems.

I have read a number of the threads regarding the 0x800CCC0F error, they all seem to deal with the inability to send or receive emails regardless of size, my problems seems to be related to the size of the attachment, or timing, or I obviously dont know what. Receiving emails is not a problem.

I have tried a number of things, routing the modem directly to the offending machine, switching cables, completely uninstalling my firewall and antivirus, all to no avail. I have run a telnet test on smtp.central.cox.net, port 25, with no error message.

Any help on this would be greatly appreciated.

Regards, Dave
Question by:novak314

Expert Comment

ID: 19614752
Hi Dave.

Do you have any anti-virus software installed which is configured to scan e-mails? Try disabling the same for some time and then check.


Assisted Solution

kmotaweh earned 300 total points
ID: 19614780
i think this is a name resolution error please recheck your dns and wins configuration and tell me if it's identical on the two computers

Author Comment

ID: 19616348

My two computers are not networked; they just share the internet connection through the hub. I think (not sure) that this takes WINS out of the picture. At any rate I can find no WINS settings on either computer.

I ran ipconfig/all and ipconfig/displaydns; the only differences I see are the physical addresses of the adapters and the IP addresses of each computer.

What I do see that is different is that the problematic computer shows the adapter as NVIDIA nForce Networking Controller #2.  The other machine does not show the #2.  Also, the network connections screen for the problematic one shows Local Area Connection 3, whereas the other just shows Local Area Connection.  This leads me to think I might have a problem in the registry, but I dont know where to look.

I have tried uninstalling the network adapter and reinstalling it with the same and different driver versions, no luck in solving the problem. When I try to uninstall the adapter from the Device Manager, it goes immediately into a reboot, without uninstalling the adapter.  I can uninstall it Safe mode.

Just a note  I use an imaging program to image my system partition before I try any of this stuff, so I can be sort of sure Im not amplifying the problem.

Regards, Dave
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Accepted Solution

ClawfootSupply earned 600 total points
ID: 19616876
It sounds almost like the attachment is taking longer to upload than the timeout set by the SMTP server, which I would expect over a slower connection, but not on a cable modem.

Have you tested your connection speed on each of the systems?  It's possible there's a problem with the TCP/IP stack, network card, network cable or port on the hub that is causing large amounts of packet loss, leading to a slower upload on the offending machine.  

Try speed tests from both the machines - http://www.speakeasy.net/speedtest/ is one of many sites that offer these for free.  The results should be about the same from either machine (make sure the other machine isn't doing anything online when you test them).  If the one having problems is substantially slower, I'd say that's the problem here.

If not, I'm not sure.

Author Comment

ID: 19617738

Thanks for your reply.  Speed on each machine is virtually identical. I have ruled out the cable and hub by running the modem cable direct to the adapter instead of the hub. I'll do some searching on TCP/IP stack, as I'm clueless on what that is or how to check it.  Bad adapter is a possibility that I've considered, but wanted to see if it was a configuration problem. I'll keep working on it.

Regards, Dave

Assisted Solution

cyberpranav earned 300 total points
ID: 19622688
Please run the system file check utility by typing in sfc /scannow. Windows may prompt you for Windows CD. After the repair is complete, restart the PC and check whether your problem is solved.


Author Comment

ID: 19629305
I installed a new PCI network card, and things are working again. No gain in speed. I've disabled the problem mobo adapter in the device manager, as there is no provision for disabling it in the bios. I still think there's a chance it's a configuration problem, but will let it rest for abit. Thanks to all for your suggestions.

Regards, Dave

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