Microsoft says it has now reached the RTM (Release To Manufacturing) stage with Windows 7, which means personal computer manufacturers such as Dell and HP now have final code

Microsoft has just announced the “release to manufacturing” of the next version of its Windows operating system. This is the last stage of the process that will end with general availability on October 22. From that point, it will be sold pre-installed on computers in shops, and as a retail package for use on existing PCs loaded with previous versions such as Windows XP and Vista.

In a conference call, Rich Reynolds, general manager of Windows, said Microsoft had delivered on its promise to release Windows 7 within thee years of Vista, and was “incredibly gratified” by the response to the code during its beta testing stage. More than 10 million people have used or are using Windows 7, and the company had captured more than 400m user sessions for analysis.

Reynolds said there were “no major changes” between the RC (release candidate) version most recently tested and the RTM version.

Microsoft is hoping to avoid the problems with third-party applications and software drivers that afflicted its last launch. Reynolds said Microsoft had learned from the Vista experience and done “a very broad outreach to partners”. Since the core architecture of Windows 7 is the same as Vista, Reynolds said Vista drivers should work. Also, the XP Mode in some versions of Windows 7 would provide compatibility with some programs based on the old XP architecture.

Ben Perrins, consumer business development manager at HP in the UK, said he expected take-up of Windows 7 to be “very high” among consumers and small businesses. “I think Microsoft is going to do a very good job of telling them why it’s good. And it is.”

Jim Ginger, director of services at Dell, said customers were “looking to make the transition” from Windows XP to “what I consider the best operating system ever”.

The launch of Windows 7 presents HP and Dell, the world’s largest PC suppliers, with a significant marketing opportunity. Sales will boom if users are persuaded to replace their old PCs with new models running Windows 7.

Both HP and Dell said they planned to ship Windows 7 on netbooks, with Dell anticipating “very high take-up”. Netbooks form the growth segment of a market that is generally depressed. According to analysis from research companies Gartner and IDC, the PC market in this year’s latest quarter is down by 3-5% compared with the same quarter last year, though the decline was smaller than they had predicted.

For HP, Perrins said touch operation was a very big part of Windows 7, and enabled the company to reach people who were not comfortable using a keyboard and mouse. “I think Windows 7 is going to make touch available to a much wider audience,” he said.

Globally, Microsoft has already sold millions of copies of Windows 7 via cut-price offers at Amazon and other stores. Most users who buy a PC running Vista before the October launch now qualify for a free copy of Windows 7, subject to shipping charges. In the US, Microsoft will also release a family pack to make it cheaper for users with multiple PCs to upgrade. However, Reynolds said he couldn’t confirm whether that was going to be available in Europe.

In Europe, Microsoft is shipping boxed copies of Windows 7 without the Internet Explorer browser, after the European Commission complained about it including IE. “Obviously, this was a hard decision, and our goal is absolutely to comply with the European Commision,” said Reynolds. Microsoft will offer “at retail, a free Internet pack” for those who want the browser. It will also offer a “migration tool” for data, to make it easier for users to switch to Windows 7.

Microsoft’s revenues from the client version of Windows fell from $4.0bn to $3.4bn in the quarter ending 31 March, partly or mainly because Microsoft charges much less for a copy of Windows XP on a netbook than it does for Vista. Microsoft hopes Windows 7 will reverse that trend. It will be bad news if it doesn’t.