The return address refused the email

I recently started a thread on Emails and Spam on the Standing Start Profits forum. One post to the thread required a reply that I think you may find valuable here.

 

"Something weird happened to me last night. I got an email from a friend with a picture embedded in the email. My ISP, Charter, won't allow embedded pictures, so they must be attached.

When I attached it and sent it to 10 friends, it got sent back to me with the following message, "the return address refused the email." Well, I was the return address. Charter had accepted the email with the picture 10 minutes before I sent it off.

Since it was a picture of 12 Nuns standing in a line, holding rifles, and the caption was "The 12 Virgins waiting in Heaven for the terrorists are not what they expect," I presume there's a filter concerning rifles or something. I emailed them but no answer."

 

After I had finished laughing at the terrorists getting their reward in heaven, I addressed the issue which is a lot more serious than Pat, the Standing Start Profits member, thought!

 

 

ISPs can choose their filtering mechanisms to suit their market. Charter is geared towards family use and they offer parental control software. This would suggest they would use a strict set of rules on spam determination.

 

The rejection of return address is about to become a very common problem. I was queried a while back on a clients email being rejected this way. He was using a google mail account, but his ISP was btinternet. The receiving mail server was trying to verify with the sending server belonging to btinternet "do you verify the existence of this mail account on your server?". (I am loosely translating into english 'cos you really do not want to read through this the way servers actually talk to each other!)

 

Of course, the btinternet server could only answer that "no, I cannot verify existence of sender@gmail.com on this server" and the mail was rejected with the message "the return address refused the email". 

 

This is a big move in the way emails are being handled and, as usual, the end users will be the last to know about it! AOL introduced this sytem nearly two years ago and were hammered in internet forums over unrouted mails. Microsoft (read MSN and Hotmail) had a deadline for introduction in November last year, and Yahoo!, EarthLink and Verizon, and others will be introducing this filter in the very near future.

 

It would be nice to be able to say that there is an easy fix for this but no, when the big ISPs got together to agree a standard implementation, they actually came away with a more splintered approach than when they started.

 

Rules for now: Always send mail through the SMTP server that owns the account in the reply to box. In other words, you@btinternet.com if you are using the btinternet mail servers as ISP. you@yourdomain.com only if you have set the outgoing mail server to be mail.yourdomain.com.

 

Many users will end up being bounced back and forth between ISP and hosting provider over this. Transporting mail has an overhead cost on a server and to avoid this many hosting providers recommend to their clients that they set their outgoing mail server to that of their ISP. If you were told to do this, change it now!

 

I bet you didn't think your post was very serious, Pat! :lol:

 

WARNING: Your ClamAV installation is OUTDATED!

Had a nice bit of regular work to do today - MailScanner Logwatch reported:

 

    WARNING: Your ClamAV installation is OUTDATED!
    WARNING: Local version: 0.90.2 Recommended version: 0.90.3
    DON'T PANIC! Read http://www.clamav.net/support/faq

 

Now I don't believe the information provided at the ClamAV support FAQ is very clear for users with a mailscanner setup, so I thought I might give a quick tutorial here.

 

First of all go to http://clamav.net and download the latest stable ClamAV distribution. While the development releases are available via svn, unfortunately, you have to go to sourceforge.net to get the production quality releases. Download the tar-ball from Sourceforge (clamav-0.90.3.tar.gz in this case). If your server is not local you will have to upload this tar-ball via ftp a directory on your server.

 

1. The first job is to back up your configuration files - I stick the copies in the backup folder for convenience,

cp /usr/local/etc/clamd.conf /backup/clamd.conf

cp /usr/local/etc/freshclam.conf /backup/freshclam.conf

 

2. In the directory in which you placed the tar-ball, you need to expand the distribution,

tar -xzf clamav-xxx.tar.gz (the xxx is replaced by the version of the distribution 0.90.3 here giving tar -xzf clamav-0.90.3.tar.gz)

 

3. Go into the expanded directory and run the install,

cd clamav-xxx (this version cd clamav-0.90.3)

./configure --disable-zlib-vcheck (parameters are not always needed - include them just in case)

make

make install

 

4. Copy your configuration files back,

cp /backup/clamd.conf /usr/local/etc/clamd.conf

cp /backup/freshclam.conf /usr/local/etc/freshclam.conf

 

5. (If you are using the perl clamav module (that would be unusual with a mailscanner install), update it now

/scripts/perlinstaller --force Mail::ClamAV) Otherwise, run freshclam to get up to date definitions,

freshclam

 

6. Restart MailScanner,

service MailScanner restart

 

You logwatch will report the outdated warning one more time as it appears to give the version details from the last time it was run (at the top, it states "Date Range Processed: yesterday"), but after that you will only see the main.cvd and daily.inc status messages.

 

You might want to bookmark this post as version 0.91.0 is coming soon!! 

 

Have a virus free day!!

 

And Now Away..

That's the last of the sites for this session and I have just checked the server logs again, so I am going to take a few hours break from the "machine".

The servers will page me if they run above my set parameters. This happened at 04:55 last night - a client account was using 95% of his disk space allowance. I increased it and phoned him this morning to upgrade his account. Better than him having downtime problems...

 

BFN

 

I'm Back

Right, that's Anthony, my 4yr old son, off to school. Well, playschool anyway - he doesn't start in "big boys school" until September. That's one of the advantages to working from home - you can adjust your schedule around your family. That's one of the dis-advantages of working from home too, - you can adjust your schedule around your family.

 

Sometimes it can be hard to motivate yourself to getting the work done. I tend to make "to do" lists, then I create targets for a working session and allow myself a "reward" if I meet my targets. I have built sixteen sites in the last ten days - but my "to do" list has grown as well. I just checked the logs on my servers while I was contemplating my next session - that's a job I do many times during my working day as I want to know about any potential problems long before it might escalate to a level that a client would notice. This seems to work as my clients are generally a happy bunch of webmasters.

 

Time to get on with it - One more site to go!!

 

POSSIBLE BREAKIN ATTEMPT!

I just had some clown from Vietnam try to break in to one of my servers on SSH.

Security Violations
=-=-=-=-=-=-=-=-=-=
Jun 15 06:25:48 host sshd(pam_unix)[29819]: authentication failure; logname= uid=0 euid=0 tty=ssh ruser= rhost=125.234.38.80  user=demo
Jun 15 06:25:48 host sshd[29819]: reverse mapping checking getaddrinfo for 125.234.38.80.adsl.viettel.vn failed - POSSIBLE BREAKIN ATTEMPT!
Jun 15 06:25:48 host sshd[29819]: User demo not allowed because listed in DenyUsers
Jun 15 06:25:50 host sshd[29819]: Failed password for invalid user demo from ::ffff:125.234.38.80 port 2583 ssh2

I would deserve whatever I got if I left Secure Access open to a Demo account!! He had to be in the Demo Cpanel or the firewall would have blocked him for not having a permitted IP Address.

 

Try it on your own host today....