High Quality Content by WIKIPEDIA articles! Windows Live OneCare (previously known as Windows OneCare Live and formerly code named A1) was a computer security and performance enhancement service developed by Microsoft for Microsoft Windows. A core technology of OneCare was the multi-platform RAV (Reliable Antivirus), which Microsoft purchased from GeCAD Software Srl in 2003, but subsequently discontinued. The software has been available as an annual paid subscription, which could be used on up to three computers.