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How can I be Spamming Myself?

The first time it happened, you were probably confused and even a bit curious, especially if you were not aware of this phenomenon of self-sent spam. A message appears in your e-mail inbox with your own e-mail address as the sender of the message, but you are pretty sure that you did not send yourself an offer for a rock-bottom mortgage rate or secrets to making millions on eBay. So then, what’s happening?
It’s not because a spammer has hijacked your e-mail account and is spamming the world using your identity but because the spammer is disguising the true sender of the e-mail with a different address, a process called e-mail spoofing, to target you specifically. In e-mail spoofing, the sender manually constructs the e-mail header and chooses which information (your e-mail address as the sender, for example) to include.
Why do the spammers do this? To get you to read the e-mail and/or click on the hyperlinks contained in the e-mail, of course. Sometimes the spammers want you to buy the products they are peddling; sometimes they want you to click on the link contained in the e-mail, which signals them that their e-mail message received a live account with a curious human at the other end, and they can then sell your e-mail address to other spammers as a potential audience for more spam from a different source. Sometimes it is for both these reasons and also to bypass filters set up through the e-mail client. Most people don’t even think about having to filter out e-mails sent to themselves from themselves.
Self-sending spam relies on human nature. A 2002 study by Hamilton, Ontario’s McMaster University revealed that e-mail’s containing shared names of the recipient had an emotional appeal that caused the recipient to read the e-mail in greater numbers than e-mail that came from sources that did not share a name with the recipient. Also, human curiosity compels the recipient to want to know how he has sent himself a spam e-mail, resulting in the recipient of self-sent spam to read the e-mail to investigate.

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Why E-Mails Bounce?

In computer jargon, a bounced e-mail is one that never arrives in the recipient's inbox and is sent back, or bounced back, to the sender with an error message that indicates to the sender that the e-mail was never successfully transmitted. But what happens when someone sends an e-mail out into cyberspace, and why do e-mails sometimes bounce back?
When a user attempts to send an e-mail, he is telling his e-mail system to look for the domain of the recipient (for example, webopedia.com) and the domain's mail server. Once the e-mail system makes contact with the recipient's mail server, the mail server looks at the message to determine if it will let the message pass through the server. If the recipient's server has predetermined that it is not accepting e-mails from the sender's address (for example, if it has blocked the address for anti-spamming purposes), the server will reject the message and it will subsequently bounce back to the sender. The message will also bounce back to the server if the mail server on the recipient's end is busy and cannot handle the request at that time. When an e-mail is returned to the sender without being accepted by the recipient's mail server, this is called a hard bounce.
Once the e-mail has been accepted by the recipient's mail server there are still ways for the message to be rejected. The mail server has to determine if the recipient (for example, webmaster@webopedia.com) actually exists within its system and if that recipient is allowed to accept e-mails. If the recipient's address does not exist on the mail server, then the message will be rejected because there is no one to deliver the message to. If the sender misspells the recipient's address (for example, qebmaster@webopedia.com) then the system will recognize this as a nonexistent address and bounce the message back. If the recipient exists but does not have enough disk space to accept the message (i.e., if his e-mail application is filled to storage capacity) then the message will bounce back to the sender. Some mail systems predetermine a maximum message size that it will accept and will automatically bounce the message if it exceeds that size and some mail systems predetermine a maximum amount of disk space the user is allowed to occupy on the server. When an e-mail is returned to the sender after it has already been accepted by the recipient's mail server, this is called a soft bounce. Some mail servers are programmed to accept incoming e-mails and store them for further analysis without initially checking to determine if the recipient exists or is even capable of receiving the message.
Occasionally, a network failure at the sender or recipient end will cause an e-mail to bounce back to the sender. Typically, a bounced e-mail returns to the sender with an explanation of why the message bounced

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Getting Rid of Spam

Spam has become ubiquitous - one of the facts of life, like taxes. Until strong anti-spam laws are passed and actually enforced, spam proliferation will continue because it's proven to reach a mass audience. If it didn't work, spammers wouldn't waste their time.
Most people, however, see spam as the scourge of e-mail and look for ways to stop it from infecting their e-mail boxes.
There are several ways to block spam from your e-mail inbox. They say prevention is the best medicine, so avoid giving out your e-mail address to unfamiliar or unknown recipients. This has become very difficult to do, however. Spammers can use software programs that troll the Internet looking for e-mail addresses, much like throwing a net in the ocean and seeing what gets caught in it. Nowadays it's almost impossible to shop online without providing a valid e-mail address. Offline stores are even asking for e-mail addresses in exchange for discounts or free merchandise. Realize that what they are doing is potentially opening the door for a flood of unsolicited e-mails. These organizations will most likely turn around and sell their list to someone else looking for valid e-mails. In these cases, it might be wise to have more than one e-mail address, one for friends, family and colleagues and another for unfamiliar sources. There are many free e-mail services in cyberspace to choose from.
However, also know that even trustworthy sources may be unwittingly shelling out your e-mail address. Ever receive an e-mail greeting card? The sender has given your e-mail to an organization that may very well be compiling e-mail lists to sell to spammers.
A second way to stop spam is to use your e-mail application's filtering features. Most e-mail applications allow you to block specific messages. When an offending e-mail comes in, set the filter to block further incoming mails from that sender.
A more aggressive approach to ridding unwanted e-mail is to report the e-mailer to the spammer's ISP. This is not always an easy task. First you must determine the spam's origins. Many of the bigger and more commercial ISPs forbid spammers from using their services and, once discovered, will actively ban the offending parties from using their services. But there are plenty of smaller ones that do not. To find the spam's origins, instruct your e-mail program to display all of the e-mail's header information. View the "Received" lines, and working from top to bottom you can often pinpoint the origin of spam. Spammers don't typically just send e-mails from their ISP to yours; that'd be too easy and apparent. Instead, they channel the e-mails through one or more ISPs in order to obfuscate the origin, but each computer that handles the e-mail will attach a "Received" line to the header. There are numerous Internet resources available for help in tracking down the source of spam.
Don't be fooled by phrases such as "to be removed from this list, click here." Spammers use these types of catch phrases to entice users to respond to the e-mails. The spammers may or may not remove your e-mail from their list. Either way you have told the spammer that your e-mail address is valid and reaches a real person. They know this because you responded and asked them to remove you from the list. This can actually be more valuable to the spammers because they can now sell your address to another spammer with the assurance that the e-mail address is legitimate. So you may have been removed from one list, but there's a good chance that you will end up on another.
Yet another way to deal with spam is to just not be bothered by it. Accept it as a fact of life. Delete the e-mails from your inbox without reading them and move on from there

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Do Cookies Compromise Security?

Cookies are messages that a Web server transmits to a Web browser so that the Web server can keep track of the user's activity on a specific Web site. The message that the Web server conveys to the browser is in the form of an HTTP header that consists of a text-only string. The text is entered into the memory of the browser. The browser in turn stores the cookie information on the hard drive so when the browser is closed and reopened at a later date the cookie information is still available.
Web sites use cookies for several different reasons:
To collect demographic information about who is visiting the Web site. Sites often use this information to track how often visitors come to the site and how long they remain on the site.
To personalize the user's experience on the Web site. Cookies can help store personal information about you so that when you return to the site you have a more personalized experience. If you have ever returned to a site and have seen your name mysteriously appear on the screen, it is because on a previous visit you gave your name to the site and it was stored in a cookie so that when you returned you would be greeted with a personal message. A good example of this is the way some online shopping sites will make recommendations to you based on previous purchases. The server keeps track of what you purchase and what items you search for and stores that information in cookies.
To monitor advertisements. Web sites will often use cookies to keep track of what ads it lets you see and how often you see ads.
Cookies do not act maliciously on computer systems. They are merely text files that can be deleted at any time - they are not plug ins nor are they programs. Cookies cannot be used to spread viruses and they cannot access your hard drive. This does not mean that cookies are not relevant to a user's privacy and anonymity on the Internet. Cookies cannot read your hard drive to find out information about you; however, any personal information that you give to a Web site, including credit card information, will most likely be stored in a cookie unless you have turned off the cookie feature in your browser. In only this way are cookies a threat to privacy. The cookie will only contain information that you freely provide to a Web site.
Cookies have six parameters that can be passed to them:
The name of the cookie.
The value of the cookie.
The expiration date of the cookie - this determines how long the cookie will remain active in your browser.
The path the cookie is valid for - this sets the URL path the cookie us valid in. Web pages outside of that path cannot use the cookie.
The domain the cookie is valid for - this takes the path parameter one step further. This makes the cookie accessible to pages on any of the servers when a site uses multiple servers in a domain.
The need for a secure connection - this indicates that the cookie can only be used under a secure server condition, such as a site using SSL.
Both Netscape and Microsoft Internet Explorer (IE) can be set to reject cookies if the user prefers to use the Internet without enabling cookies to be stored. In Netscape, follow the Edit/Preferences/Advanced menu and in IE, follow the Tools/Internet Options/Security menu to set cookie preferences.

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Are Deleted Files Completely Erased?

A common misconception when deleting files is that they are completely removed from the hard drive. However, users should be aware that highly sensitive data can still be retrieved from a hard drive even after the files have been deleted because the data is not really gone. Files that are moved to the recycle bin (on PCs) or the trash can (on Macs) stay in those folders until the user empties the recycle bin or trash can. Once they have been deleted from those folders, they are still located in the hard drive and can be retrieved with the right software.
Any time that a file is deleted from a hard drive, it is not erased. What is erased is the bit of information that points to the location of the file on the hard drive. The operating system uses these pointers to build the directory tree structure (the file allocation table), which consists of the pointers for every other file on the hard drive. When the pointer is erased, the file essentially becomes invisible to the operating system. The file still exists; the operating system just doesn't know how to find it. It is, however, relatively easy to retrieve deleted files with the right software.
The only way to completely erase a file with no trace is to overwrite the data. The operating system will eventually overwrite files that have no pointers in the directory tree structure, so the longer an unpointed file remains in the hard drive the greater the probability that it has been overwritten. There are also many "file erasing" software products currently on the market that will automatically permanently erase files by overwriting them.

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