Windows Server 2003, Microsoft's first ultra-successful server operating system, will retire in six months, a deadline that many companies will miss, experts said today."If it's not broke, don't fix it," said David Mayer, the director of Microsoft Solutions for Insight, a major IT services provider, when asked why Windows Server 2003 has hung on even as its support deadline looms. "It was the first really mainstream server from Microsoft, a really solid OS, and gave Microsoft a lot of credibility [in server software]." Microsoft will terminate security updates for Server 2003 on July 14, ending the product's support lifecycle. The company launched Server 2003 in April 2000. Like Windows XP, on which it was based, it will have been supported years longer than the usual decade.