Those same experts have split on whether Microsoft will extend Windows XP's support to protect what increasingly looks to be a major chunk of Windows users. But Microsoft has not signaled any desire to do so.
Granted, Microsoft will have supported XP for 12 years and 5 months, or about two-and-a-half years longer than its usual decade. That will be a record, as XP this month tied the previous Methuselah, Windows NT, which received 11 years and five months of support.
But Microsoft could still rethink its XP policy, and mimic rival Apple, which has continued to support OS X Snow Leopard, an operating system that, like XP, maintains a robust usage share.
Apple, which has never spelled out its security update policies, typically has stopped supporting "n-2," where "n" is the most current edition of OS X, around the time it releases "n."
Snow Leopard -- "n-2" in that formula, having been superseded by Lion and Mountain Lion, the latter representing "n" -- has continued to receive security updates, most recently on March 14, or about eight months after Mountain Lion's launch.
By continuing to update Snow Leopard, which powered 27% of all Macs last month, Apple patched 91% of all Macs last month.
Microsoft could do even better -- cover 96% of all current Windows PCs -- by continuing to support XP after April 2014.
But one expert thought that very unlikely. "I think they have to draw a line in the sand," said John Pescatore, then an analyst with Gartner, now with the SANS Institute, in an interview last December. "They've supported XP longer than anything else, so they'd be pretty clean from the moral end."
To track how long XP has before retirement, users can browse to an online countdown clock maintained by Camwood, a U.K. firm that specializes in helping businesses migrate to newer operating systems.
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