The letters which are deemed by the company to be "educational" are being sent to users in conjunction with the BPI, the body which represents the UK record industry.
While 800 people seems like a small and rather pointless number to send warnings out to, the BPI believes that thousands more will be sent out in the coming weeks.
This is part of a 10-week campaign that's been put in place to highlight the illegalities of downloading music for free.
Although Virgin Media and the BPI is adamant that the campaign is about education and not law-enforcement - so nobody will actually lose their broadband connection over the letters - the envelopes the letters come in are branded with the words: 'Important. If you don't read this, your broadband could be disconnected.'
Speaking to the BBC, Virgin Media has said that this is a mistake, and that the envelopes would be reviewed mid-August.
This 'mistake' comes after Virgin Media was criticised yesterday about the wording in one of its advertising campaigns. Something tell us the company needs to employ a sub-editor and fast.
Although the BPI wants all ISPs to sign up to the campaign, only Virgin Media has so far signed up.
So, if you are worried about the stance Virgin Media is taking on this here's our choice of five ISPs currently not taking part in the BPI crackdown: BT, AOL Broadband, Tiscali, Orange and Sky.