The active users out of the 350 million people with Windows Live Hotmail accounts, along with spammers, send an average of 8 billion emails per day, Microsoft revealed. In fact, the vast majority of messages that are headed to Windows Live Hotmail accounts are in fact spam. According to Dick Craddock, Group Program Manager, Windows Live Hotmail, only 2.5 billion messages actually make it into the inboxes of customers. The math is rather simple at this point in time.
Microsoft is filtering on average some 5.5 billion messages, all of which unwanted emails that never make it to the 1.3 billion inboxes of the service.
“We know (from measuring after the fact) that about 110 million messages that get delivered are spam. So, that's a bit less than 5%: 110 million ÷ 2,500 million = 0.044, or less than 5%. We filter out all but 110 million spam messages out of 5.5 billion we receive each day, so that means we're filtering out 98% of spam: 110 million ÷ 5,500 million = 0.002, or about 2%,” Craddock stated
The statistics offered by Craddock are a tad different than those shared by one of his colleagues just ahead of Christmas. Arthur de Haan, responsible for Test and System Engineering in Windows Live, noted that Microsoft handled over 3 billion messages
a day and was filtering more than 1 billion spam emails. It sounds like Microsoft needs to get its Windows Live Hotmail statistics right.