Microsoft is to use spam-catching technology to clean up users' inboxes.
Subscribers to the web-based email system receive more than one billion pieces of junk email between them daily, according to a survey by MSN.
And Microsoft has estimated that 80 per cent of messages that pass through the company's servers are junk.
Microsoft has signed a deal Brightmail, which claims a 90 per cent success rate for its product. It generates 200 million decoy email addresses and posts them on newsgroups and websites that its business intelligence division has shown to generate spam.
Brightmail's Probe Network, which sits at the simple mail transfer protocol gateway, identifes the characteristics of the spam collected by the decoy addresses. The information is sent to Brightmail software on the customer's server, which can then identify and delete spam.
A Brightmail spokesman told vnunet.com that the company constantly updates its software so it can keep abreast of emerging trends. "We look on this fight as guerrilla warfare," he said.
MSN and Brightmail would not give a definite date for full deployment of the service but said it would be later this autumn.
Users of the free Hotmail service should not see the spam at all. Customers of the Hotmail subscription service will have spam directed to a junk folder where they can view it to check no legitimate mail has got caught.
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