In September 2007, Microsoft pushed back the date for when OEMs (original equipment manufacturers) could install and sell XP on PCs until July 31, 2008, from the original date of Jan. 31 of this year. At the same time, it extended the XP cut-off date for system builders until Jan. 31, 2009

XP has an even longer shelf life for the emerging ultra-low-cost PC (ULCPC) market, another concession Microsoft had to make because Vista's hardware footprint was too big for these machines. In April the company said it would be available for OEMs to install on ULCPCs either until June 30, 2010, or one year after the availability of Windows 7, whichever comes first.