MONTREAL — Consumers buying personal computers in the coming months will likely end up with Microsoft's reputation-bruised Windows Vista operating system instead of the older XP system, whether they like it or not.

As of June 30, Microsoft will no longer ship Windows XP to retailers and to hardware companies that make PCs, forcing an eventual switch to Vista. "Does that mean (XP) will instantly disappear off the shelves or off PCs? No," said Microsoft Corp. Canada's Elliot Katz.

"Inventories have to clear for hardware manufacturers, inventories have to clear at retail," said Katz, senior product manager for Windows clients.

Windows Vista came out in January 2007, but Katz said Microsoft has left the XP line in the marketplace longer than it intended due to consumer demand.

"That's because our consumers were asking us to do so," he said.

"The very typical situation is when any kind of change is introduced, people are reluctant to change."

Windows XP was introduced to consumers on Dec. 31, 2001, and has found much more favour among computer users than its newer cousin over its lifetime. The InfoWorld information technology website hosts an online petition to save it and extend it beyond the June 30 deadline.

Volleys of criticism have been launched at Vista with its performance and security being taken to task on tech blogs and in news articles.

Apple has used this to its advantage with its "Get A Mac" ads that have poked fun at Vista for such things such as its security prompts.

U.S.-based analyst Michael Silver said Vista gives consumers "a pretty good experience" but that message seems to be lost.

"At this point, we think Vista's reputation is worse than the product is, actually," Silver said from New York.

The debate between Microsoft's Vista and XP operating systems ends up giving Apple's Mac "something to gloat about," said Silver, who's with Gartner Inc., an information technology research and advisory company.

Katz said Vista offer feature improvements such as better security to protect photos and videos, strengthened parental controls and the ability to make high-definition movies.

Window XP support ends on April 14, 2009, he said. Security updates for Windows XP will continue to be made available, as necessary, until April 8, 2014.

A computer operating system is the interface between the hardware and the software. It interprets software requests and is the key to making the hardware operate.

Among the most popular on today's desktop computers are Microsoft's Windows family, Apple's Mac OS and Linux.

An operating system can also help make a computer user friendly. For example, you put in a DVD and the operating system enables you to view what's on the DVD and watch it on your computer screen.

Eric Lancheres, whose business repairs computers for consumers and enterprises, said when Vista was first introduced it was often installed on older computers.

"People installed it on machines that were not able to run it properly," Lancheres, owner of Computer Repair Montreal.

"A lot of people had a lot of inconveniences, bugs, and it ran a bit slower," he said.

It's the Vista security feature called User Account Control (UAC) that has generated criticism and Katz acknowledged it causes "a little inconvenience."

"It's just verifying that the website you want to go to, or the application you want to install, or the change that you want to make to the operating system is something you want to do intentionally. Once you've had your PC running for a little bit, those prompts and those messages no longer pop up."

Lancheres called Vista's security prompts "exceedingly annoying" and said people usually try to disable them right away or "dismiss" Vista as an operating system because of them.

Silver said he thinks Microsoft hasn't made it clear enough what sets Vista apart from XP.

"It's really not coming through to people what the benefits are," said Silver, who's with Gartner's client computing group.

"It's hard for Microsoft to quantify something like better security, or even explain it, because so much of it is buried deep in the operating system.

"Microsoft has spent a lot of money advertising Vista and most folks really can't say what those commercials were or what they were about, or identify them."

The Redmond, Wash., software giant has run "See the Difference" and "Wow" themed commercials to promote Vista's new features.

Katz said Microsoft has sold about 140 million copies of Vista.

Microsoft is working on its next version of Windows, which is expected to reach the consumer marketplace in 2010.