The rising tide of spam messages is starting to seriously inconvenience British businesses, a survey has found.
Some spam is easy to spot
It showed that almost 20% of companies reported that more than half of all the e-mail messages they received were unwanted junk e-mail.
Despite the growing problem, only a fifth of firms were taking active steps to filter the junk, said the report.
The UK government survey is conducted every two years to see what UK firms regard as computer security threats.
Junking the junk
Most people with an e-mail address are familiar with spam messages that offer all kinds of herbal cures, impotence drugs and other dodgy goods via e-mail.
The Information Security Breaches Survey, carried out for the Department of Trade and Industry, has found that coping with spam is rapidly becoming a problem for many firms.
"Spam hits businesses in a number of ways," said Andrew Beard, from survey co-ordinator PricewaterhouseCoopers.
"They can be victims when their e-mail and network services are degraded," he said.
"But they can also unwittingly contribute to the problem if they allow poorly secured mail servers to be used by the spammers as 'relays' to spread their messages to other organisations."
Although many firms are seeing more spam, businesses are split on how big a problem it is.
About 10% of those questioned said spam was a major issue, while one-third said it was not a problem at all.
It found that large companies were much more likely, 44%, to have deployed anti-spam tools than smaller firms.
The study said there could be two reasons for this difference.
Firstly, few small firms have enough spare cash to afford anti-spam measures and, secondly, many are unaware that good filtering systems exist.
Many of those responding said media focus on spam portrayed it as a bigger problem than it actually was.
The final full results of the survey will be launched at the InfoSecurity Europe trade show taking place in London from 27-29 April.