Microsoft has apologised to a British man it had accused of sending out huge amounts of junk email, or 'spam'.
No spammer: Mr Grainger had protested his innocence
The software giant issued an "unreserved apology" to Simon Grainger from Merseyside, whom it had served with a writ, accusing him of stealing e-mail addresses of its customers to send them spam.
Mr Grainger was one of 15 people targeted by the company in a high-profile attack against the rising tide of junk email.
But Microsoft has now, two months later, admitted it was a case of mistaken identity.
In a statement to the BBC in June, Microsoft said it had taken legal action "against a background of misuse of a domain name registered in Mr Grainger's name".
But Mr Grainger said the company had made no attempt to contact him before serving him with the writ by post.
Microsoft did, however, leave a window of opportunity open.
It said in a statement:
"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."
Mr Grainger said he thought he had 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," he told the BBC.
Microsoft had claimed its anti-spam investigation team came with a background in law enforcement.
And Mr Grainger was warned it could cost a five-figure sum to fight the case.
But one of the UK's most prominent anti-spam organisations, Spamhaus, said it always believed Microsoft had wrongly accused the 43-year old.
After listening to his story, Spamhaus's Steve Linford 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 also checked his worldwide database of spammers: "These people always leave a trace but we can find nothing relating to Mr Grainger."