A variety of different elements weaken your corporate and personal email system and while some are widely known - such as email viruses - others tend to be ignored. Emails carrying offensive messages or confidential corporate information can create immense inconvenience and expense for a company that has not equipped its mail server with the appropriate tools. The same goes for spammers who use the email system at work to send thousands of unsolicited email messages. And what about the vast damage and time-loss caused by email viruses, which seem are making ever more frequent appearances these days?

Some companies lull themselves into a false sense of security upon installing a firewall. This is a wise step to protect their intranet, but it is not enough: Firewalls prevent network access by unauthorized users. But they do not check the content of mail being sent and received by those authorized to use the system, for instance. More targeted measures are needed to counteract this and other security loopholes in a corporate network.

Information leaks
Organizations often fail to acknowledge that there is a greater risk of crucial data being stolen from within the company rather than from outside.

Various studies have shown how employees use email to send out confidential corporate information. Be it because they are disgruntled and revengeful, or because they fail to realize the potentially harmful impact of such a practice, employees use email to share sensitive data that was officially intended to remain in-house.

FBI statistics, for example, reveal that among Fortune 500 companies, most data thefts in 1998 were by internal users. Again, research results carried in PC Week in March 1999 report that, out of 800 workers surveyed, 21-31% admitted to sending confidential information - like financial or product data - to recipients outside the company by email. Ten per cent of those surveyed disclosed that they had received email containing company-confidential information.

Malicious or offensive content
Emails carrying sensitive information, or unsolicited mail messages sent out by corporate users are not the only problem a company has to tackle with regard to employees' email use. Emails sent by staff containing racist, sexist or other offensive material could prove equally troublesome, not to mention embarrassing - and expensive!

This factor hit the headlines during the much-publicized antitrust case against Microsoft Corp., when the US government presented as evidence the contents of emails written by top Microsoft executives describing plans to topple competitors. On a similar note, Chevron recently had to pay $2.2 million to settle a lawsuit resulting from an email message bearing sexist contents.

Under British law, employers are held responsible for emails written by employees in the course of their employment, whether or not the employer consented to the mail. The insurance company Norwich Union was asked to pay $450,000 in an out-of-court settlement as a result of emailed comments relating to competition.

Besides, offensive emails can cause considerable damage to the work environment simply by generating an unpleasant, hostile or unprofessional atmosphere.

Viruses
Viruses are a major email security hazard that companies simply cannot afford to ignore. Over 11,000 different computer viruses exist to date and some 300 new ones are created each month. Their effects range from negligible to bothersome to destructive.

The extent of the problem is so great that today many companies have even begun to prohibit the use of email attachments, as this is where viruses are often embedded. Unless forewarned, users are generally unaware that they have received a virus until they open the infected attachment. By this time, it is too late: the virus is activated and starts to take over, completely infecting the hard drive and the messaging network.

The danger of viruses transmitted through macros, another common form of virus transmission, is that they allow the user to continue working and sharing documents. This way, the virus spreads faster, infecting more and more users. One such macro virus, known as Melissa, reared its ugly head on March 26, 1999. Melissa forced organizations the world over - among them Microsoft and Intel - to suspend all email transactions. This may well have been an effective response to the new viral onslaught, when timely action was taken - but it also signified incalculable productivity loss, despite stemming data loss. As a result, Melissa left a huge dent in corporate coffers: "It is responsible for millions of dollars worth of damage", an April 1999 issue of InfoWorld reported.

Other fiercely destructive viruses followed fast on Melissa's trail, such as the Chernobyl (CIH) virus and the Explore Worm, both of which wipe out files, resulting in data loss. Again, companies like Microsoft, Intel, Boeing and Forrester Research were reported in the press as having shut down their mail servers when hit by the Explore Worm outbreak in June 1999. And, as if all this were not enough, anti-virus researchers predict that more damaging email viruses are yet to come.

Spam
About 90 per cent of email users receive spam - or unsolicited commercial mail - at least once a week, a survey conducted by the Gartner Group shows. The research results, issued in June 1999, revealed that almost half those surveyed were spammed six or more times a week. The study surveyed 13,000 email users.

Although the U.S. Congress and state legislatures are seeking to ban spam, and the Federal Trade Commission sues spammers whose junk mail deceives consumers, unwanted mail is on the increase.

As well as consuming bandwidth and slowing down email systems, spam is a frustrating time-waster, forcing employees to sift through and delete mounds of junk mail. It also proves irritating and offensive to recipients who feel their privacy has been invaded. However, there is a third aspect to spam: it constitutes a security hazard.

Spammers can use a corporate mail server to send out their unsolicited messages, often bringing trouble upon the unwitting organization. Virgin Net recently underwent such an experience when one of its subscribers apparently used its network to send out 250,000 junk messages. As a result of this individual's actions, Virgin Net was put onto the Real-time Blackhole List (RBL), an undesirable listing which leads other ISPs to reject mail coming from that company.