Microsoft has pushed back the automatic distribution of Windows XP Service Pack 2 (SP2) to allow business users more time to prepare their systems for the update - or choose to skip it entirely.

The software maker now has different schedules for pushing out SP2 to the two editions of Windows XP. Users of the Home Edition should start getting the update this Wednesday, while the Professional Edition won't be updated until a week later, on August 25, according to an e-mail Microsoft sent to select users over the weekend.

Microsoft advises consumers to enable Automatic Updates in Windows XP to patch their systems, but recommends businesses use patch management tools such as its Systems Management Server and Software Update Services or third-party products.

Taken off guard by the large number of business customers who rely on Automatic Updates, Microsoft last week made available a mechanism to temporary block the download of SP2 on XP systems. The updated release schedule is meant to give users more time to put that SP2 block in place.

"Last week, we received feedback from our corporate customers that they would like more time to put this temporary blocking mechanism into place. Based on that feedback, we have altered the delivery schedule of Windows XP SP2," Microsoft wrote to its customers.

Microsoft has been criticised in the past over SP2 delays. But this time the schedule change is intended to address the requests of users worried that the update will cause chaos because of compatibility problems.

"Microsoft finally sees the issues that we see from the corporate world about how serious this is," says Thomas Smith, manager of desktop engineering at a large Texas-based company. Smith manages about 5000 desktops running Windows XP Professional Edition, most of which use Automatic Updates.

Smith is happy about the reprieve, but he feels Microsoft's decision to automatically push out SP2 is wrong.

"I think it should never go out as a critical patch," he says. Instead, Microsoft should have offered feature updates that users could decide to install on their own terms, Smith adds.

SP2 is more than the usual roll-up of bug fixes and updates; it makes significant changes to Windows in the name of increased security. As a result, SP2 can render existing applications inoperable. Because of those changes, many businesses are holding off on installing the service pack and are taking time for testing. Automatic Updates initially did not give users that flexibility.

Microsoft has had to issue warnings that several of its products don't work with SP2. These products include its CRM (customer relationship management) product and Baseline Security Analyzer tool, which both need updates to work with SP2.