Web Design Discussion

Recently I was unable to send email from info@isitebuild.com. At first I thought my email messages were too large to send, however I traced the problem to my high speed cable provider…Comcast. I needed to use Port 26 from my web host instead of 25 which is the port Comcast uses.

Here’s the error I got:

An unknown error has occurred. Subject ‘Re: Need to Know [2/2]‘, Account: ‘info’, Server: ‘mail.isitebuild.com’, Protocol: SMTP, Port: 25, Secure(SSL): No, Error Number: 0×800CCC0B

To find the solution I ran a tracert command.

What is Tracert?

Tracert (also known as traceroute) is a Windows based tool that checks how many “hops” (transfers through other computers on a network) it takes for your computer to contact another computer. It allows you to trace the packet route between two computers.

How Tracert Works

You can use traceroute if you know the other computer’s IP address, web site address, or name.

How to Access Tracert

1. From the Start menu, select Run… .

2. In the “Open:” box, type cmd (Windows NT, 2000, and XP) or command (Windows 95, 98, and Me).

3. At the command prompt, enter tracert computer , where computer the is or the IP address, name, or web site of the computer you are trying to access.

In my case, I ran the following tracert commands on my PC to find a solution (using web address):

tracert isitebuild.com
telnet isitebuild.com 25 and got the following output:

http://www.drostdesigns.com/wp-content/themes/laila/images/tracert.gif

In the first column you see the hop count. This represents the number of stops your information has made along the route to attempt to contact the other computer. The next three columns are the round-trip times in milliseconds for three different attempts to reach the destination. The last column is the name of the host that responded to the request.

The above example shows that a computer user on comcast.net ran a traceroute to www.isitebuild.com. It shows bad requests went to comcast.net for several other hops. On the seventh hop, the request left the Comcast network and went to the att.net network. On the ninth hop, the request went to the gblx.net network. On the tenth hop, the request “timed out.” This means there was some problem between the comcast.net network and the isitebuild.com network.

Run the Telnet Command

The telnet command showed what server my web site resides on and provided an explanation of the error message.

http://www.drostdesigns.com/wp-content/themes/laila/images/telnet.gif

Solution with explanation.

1. Comcast blocks port 25 from sending mail.

2. In my outgoing mail server settings, instead of using default 25, I should change it to port 26 (for isitebuild.com)

3. Comcast only allows outgoing 25 on their own mail server, so I should use port 25 for them, and 26 for my own mail servers.

Conclusion.

Running a tracert and telent command from your computer is a fast way of monitoring your web site so you can rapidly troubleshoot and therefore remedy the situation.

This entry was posted on Monday, October 9th, 2006 at 11:11 am and is filed under Web Design . You can follow any responses to this entry through the RSS 2.0 feed. You can leave a response, or trackback from your own site.