JUNK e-mails have become one of the most stressful aspects of working life for many people in Worcestershire and Herefordshire.

But many people are unwittingly making things worse by replying to the so-called "spam" messages, according to a new report.

A poll of 1,000 computer users found that one in four had been fooled into opening unwanted messages believing them to be genuine.

Internet provider Yahoo! has launched an advertising campaign, including messages on rubbish trucks and bin bags, giving tips on how to tackle junk e-mails.

The initiative is part of a world-wide initiative called Dump The Junk, aimed at advising people never to reply to junk e-mails or forward them to friends.

John Webb, head of Yahoo! Mail in the UK, said most people did not know the best way to tackle the problem

"Our research shows that many British internet surfers don't have the knowledge to tackle junk mail effectively with over half of Britons actually helping to perpetuate the junk mail cycle."

An estimated 40 per cent of e-mails sent world-wide are junk, costing firms huge amounts of money in delays and lost production.