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| Filtering Email |
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Ok your email is becoming a hassle mostly due to huge amounts of Junk Mail filling your email box to overflowing? The first thing I strongly suggest to anyone is to use a mailer. If you have a POP3 ( Post Office Protocol 3 ) mail server as most ISPs operate you should be able to use most commonly used mailer programs with it. I personally use Outlook Express ( please dont laugh ) which more than serves my needs but many of the functions I will mention can also be adapted to MS Outlook, Incredimail, and perhaps others such as Netscape Mail and Eudora. I like Outlook Express as it seems to function well and if you are up on the security settings it has never been a problem for me. If you are using or choose to use MS Outlook Express or Outlook you may wish to check to make sure your security settings good. I recently found this email security test site which seems to do a reasonably good job of testing. I would however make sure you do not check to get the newsletter if you do not want yet another piece of spam. http://www.gfi.com/emailsecuritytest/ However this section is not about security per say, it is more about how to decrease the dreaded junk mail ( spam ) you find in your email. Well the first thing you need to understand is Bulk email operations do this for MONEY. They learn and use all the tricks they can get to gleen email addresses from websites, chain letters, forwards, ecards, and what appears to be a great web offer on some site that asks for your email. If you want to limit the spam you get, the first defence is not to let them get your email address. This is best done by not giving it out to anyone except your closest friends and then only with the understanding that it will be not used with forwards or bulk mailings. Even ecards tend to provide some bulk mailer with a pair of new email addresses to email too. Assuming you have not already let that cat out of the bag so to speak, you can often set up a junk mail box on the web somewhere that you can check only when you really care to sort through all the junk mail. Look for free email on a server that has a good size storage limit such as Yahoo.com.. If you want to sign up for a free offer or need to give an email out for some dirty questionable job then direct them to that web based email, and not the one on your ISP. The next thing to do is if you use mailer is to set up filter to remove the bulk of the content that comes in that is junk mail. Outlook Express has a filter system but you need to add the strings it is to filter as needed. At best Outlook Express's filters will miss a high percentage of spam unless you use an external filtering program. To make your own filters in Outlook Express will need to look at the Properties of the SPAM you receive on a regular basis. As shown below to see the properties of an email you would right click on the email header you wish to view the properties from and then right click your mouse then select properties. 
This will show you the basic header information of the email. It
however is often a good idea to go one stept further and also view
the message source
(
click here for an example of a message source
)
and look at
the first line for the server it started from. In most cases you will
see two or three servers used if you keep seeing the same junk mail
over and over. Generally things like @specialoffers.com or
@vminman.com are two of the more popular ones who stuffed my box
until I took measures to stop them. I am sure there are many many
more operations out there. You will however soon see a trend in where
the email is coming from.
Generally these bulk mail
operations change the from address each time they mail something. For
example, one time it may be abcd@specialoffers.com and the next time
it may be dcba@specialoffers.com and so on.
Needless to say they can make many more addresses this way than you can block by using the block sender command with Outlook Express. ( I know I tried to block many of them ) however what many do not know is that you can edit the blocked senders. You can do this by clicking on Tools- Messages Rules - Mail. Then click on Blocked Senders and pick out one of the addresses that is from the bulk mailer server you wish to block for example purposes say it says @specialoffers.com on the end of it. Then click the modify button and edit off the first part of the address. As an example, remove the ABCD from the address ABCD@specialoffers.com then click ok. This should then block all email that comes from @specialoffers.com to the deleted file which you can dump from time to time. Sadly the filers in Outlook Express do not seem to be as effective at blocking words in the body or subject areas, as you can generally add in text from subjects and bodies and still see some blocked words get through. In part because some bulk mail uses image files for the content which they know many would block, or they may encode the text so that it may not be readable by the filter. 
You may even be able to block
IP Addresses if you find the same one showing up with different email
names on it. To do this click on Tools, Messages Rules, then Blocked
Senders, then Add, type in the IP address you wish to block. Keep in
mind however that many can and do change their IP addresses with new
connections to the internet so blocking mail this way may not be as
effective unless you are fairly sure they are on a fixed address.
Lately I have found that the spammers are to the point of getting around most
filters with a given email. Generally this is done by either changing the
entire @xxxx.com or @xxxx.net part of the address.
At times you may also see the same email get thru your filters again and
again. From what I have seen this must be a fault in the filter used on many
mailers, particularly Outlook Express. I believe it is done by placing a
"boundry" command in the header and then setting the boundry for the
email beyond the end /html tag.
You may have some luck in stopping the same message over and over from
getting thru your filter by trying this. Right click on the header line of the
offending email and selecting properties. The in most cases you can view the
source of this email by clicking on the view source button you should see
there.
Go look in the header area of the source of the email and you will see a line
that says:
Note most of this applies to Outlook Express but can often be easily adapted to other mailers. If you currently do not use a mailer, most Internet Explorer versions from 5.x up have Outlook Express available. To install it if you do not have it currently installed you would just go to the control panel in most cases, and then to the ADD/REMOVE programs and then Windows Componants where it should be listed as a Windows part you can add but clicking in the check box and then selecting apply. If this does not work you can go to the Microsoft Internet Explorer Home Page and download the current IE version which should install Outlook Express also at that time. If you prefer not to use Outlook Express, there are several other mailer about and most can be found on www.tucows.com by typing in mailers or email clients in the site search arguement. For hotmail as well as other web based email operations, they have the filters included in their web based interface usually. Typically under the options tab. Since these vary from site to site, I am just going to go through the process with hotmail.com and you will need to adapt accordingly if you are using another service. Spam Bot Blocking on hotmail.com
Dealing with Email Attachments I am sure some will not like this solution but I do not accept any attachments. They just are not worth the trouble and compromise system security too much to accept. If someone wants to send me a file, they better just send me a link on a webserver or tell me before they send it or it will be trapped by my security settings or just not downloaded and then deleted. However here is something you can do if you do not wish to go to the lengths I have.
I would normally suggest making a new folder for these and calling it attachments. This should then move the message with the attachment to that folder and not leave it in your inbox. Then you can use caution in opening such messages as you see fit such as only opening them offline and with virus scanner active or what have you. If you have a problem with people sending you virus payloads you may wish to just leave these on the server. It should in most cases download the header of the message so you know they are there but not allow the payload to be placed on your system. If you have a problem with hidden payloads you may wish to move them to an attachment folder and then start a program like AnalogX Script Defender before you open of the message content found there which should prevent any scripts from being run without asking your permission first. I personally just run the highest security on my email and not bother with them. Most anyone can get a free webspace which you can transfer files up to 1mb back and forth on pretty easy and pound out some very basic HTML to make it look pretty nice. It really is a much more secure way to do things. Blocking with Subject and Body Strings : Note for this purpose most areas where is says Subject can have Body used instead. Or in otherwords if you wish to block a given word out of the Subject use the Subject block in the Message Rules area or if you wish for it to attempt to scan the Body of the message for a given string of Text you should use the Body block link in the Message Rules section.
This is why I said I can show you the process of how to do this but you will have to construct it as you would wish it to be. There is however a few more things to say. Most of these items work on POP3 mail servers with Outlook Express. I cannot speak to what the limits or functions are on other programs. Outlook Express does NOT apply message rules to hotmail. You must use the filter on the hotmail site to limit spam on hotmail. ( it is pretty effective except on Microsofts own spam of course if you set it to the highest setting ) Most mail servers have a server based filter also which you can set up more or less using the same general guidelines as I have mentioned above. As with any filter however you can find yourself filtering out some email you would wish to read. Keep in mind that you should mention to people you talk to you are filtering your email and how so they will know what to avoid sending and getting caught in the mail filter. If you wish to edit the message rules you have made it is not hard to do that either. ( it is also why you would see I mentioned to keep your message rule count low ) To edit them go to Outlook Express's TOOLBAR and select TOOLS then Editi Message Rules, then select Mail in most cases. You will be shown Message Rule 1 through whatever number you have. You can edit them or delete them or move them up or down the list as to where you wish to have them applied. Note that the higher up the list the sooner the rule will be applied. ( so if you have attachments at the top of the list it would move any attachment to your attachment folder say and not delete it from the server if you had that as a rule but further down the list ) With some practice and a bit of thinking most can get a pretty effective set of Message rules in place that will GREATLY limit the amount of spam you have to deal with. Here is something I just run across that I found rather helpful and I use it at this time myself. Call it a recommended item for those with POP3 access and using a mailer... ( thanks to Megan at Tech TV ) One problem however with the use of SpamPal is that it does not work with all AV Software. I personally did not get it to work well with PC-cillin2002 due to a port conflict. It may however work fine with some other AV Software. http://www.spampal.us/download.html http://www.spampal.org.uk/download.html SOPHOS AntiSpam Whitepapers MailWasher free use on one Email account. Tech TV download of the day archive ( opens in a new browser window ) Here is a link to the Federal Trade Commission Spam Information Page. http://www.ftc.gov/bcp/conline/edcams/spam/index.html ( opens in a new browser window )
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If you look at the end of your message source you will also see that the
content between the quotes on the header will also be at the end of your email.
This content does not stay the same for all emails but it generally will be
the same for a given email which you may well see over and over slip thru your
filters. This boundry may or may not be this long but generally these emails
are all the same and use this same type of trick to get around the filter. If
you add the content seen between the quotes which would likely be somewhat like
the example above to a filter to block a given string in the Body of the
message, and have your mailer delete it or do whatever you wish to prevent it
from being a problem for you. This generally will stop the repeated display of
that given email until such time as they rewrite the boundry tag section to
include a new number. Sometimes this works for a long time other times it will
only be effective for a day or so. Generally speaking blocking the entire
content line does not seem to work ( such as blocking the content
type="mixed-multipart" ) with the filters in Outlook Express anyway.