A British man accused by Microsoft of spamming has told the BBC it is a case of mistaken identity and he will fight to clear his name.
Simon Grainger, who lives on Merseyside, was one of 15 people around the world targeted by the company in what is the most high-profile attack so far on the huge wave of unwanted e-mail clogging up the internet.
But the 43-year-old telecoms engineer insists that, in his case at least, Microsoft has got the wrong man - and he is now in a David and Goliath contest with the US software giant.
Gates says he 'hates' spam
In a statement to the BBC, Microsoft said it had taken legal action "against a background of misuse of a domain name registered in Mr Grainger's name".
But it did leave open the possibility that it had made a mistake.
"In the event that there is persuasive evidence supporting Mr Grainger's assertions, we would be very happy to consider it and team up with Mr Grainger to discover the true identity of the perpetrators," the statement said.
The first the Grainger family heard of Microsoft's legal onslaught was seven o'clock on Tuesday morning last week when there was a knock on the door of their Merseyside home.
Fourteen-year-old Kerry answered and accepted an envelope for her father.
But when Simon Grainger got home and opened the package, he found a writ from one of the world's most powerful corporations.
Microsoft was alleging that he was a spammer and had been harvesting e-mail addresses from its MSN site.
Mr Grainger does have three websites - but he says they are used for his teenage daughter's homepage and for a local flying club, not for spamming.
But he believes he has been targeted because a domain name he bought last year may have been used in spam attacks by a previous owner.
"When I activated it, it was suddenly inundated with spam - and I took it offline."
When it unveiled its war against spam, Microsoft boasted of its investigation team with a background in law enforcement.
But Mr Grainger says the company made no attempt to contact him before the writ was served.
As he and his wife Karen talked to me in the living room of their compact three-bedroom house on a quiet estate, they seemed bewildered and frightened by the prospect of a lengthy legal battle with a very wealthy and powerful opponent.
They are employing a local solicitor in Birkenhead, while Microsoft is represented by Mishcon de Reya, the law firm that once acted for Princess Diana.
I'm 98% convinced that Microsoft have got the wrong man
"We've been told it could cost us a five-figure sum to fight this," said Mr Grainger.
"They've got so much money," added his wife Karen. "We've got three daughters and no excess cash. We're asking ourselves how are we going to take these people on and prove that Simon is innocent. But it's got to be done."
The Graingers pointed out that they had gone to great efforts to protect their children from junk e-mail, which is often pornographic, and insisted they hated spam.
'No trace' of spamming
The BBC put Mr Grainger in touch with one of the UK's most prominent anti-spam organisations.
After listening to his story Steve Linford of Spamhaus said, "I'm 98% convinced that Microsoft has got the wrong man."
Mr Linford said his organisation had been tracking spamming activity from the domain name acquired by Simon Grainger in October 2002 - but it had ceased before he bought it.
He has checked his worldwide database of spammers: "These people always leave a trace but we can find nothing relating to Mr Grainger."
Microsoft said it was "committed to addressing the spam problem on behalf of all consumers" and had not received formal notice that Mr Grainger was taking legal action to defend himself.