Microsoft has pushed the Office 2007 SP1 update to some users automatically, despite the software giant's initial claims that Windows' Automatic Update service would not push the service pack to users for several months.

Anyone running a preview copy of Windows Vista Service Pack 1 (SP1), which was made available to all comers only on Wednesday, will receive the Office 2007 upgrade automatically, Microsoft has confirmed. Users of other in-beta Microsoft products, including Windows XP SP3, which is still in limited testing, will also be hit by the Office update, which weighs in at almost 220MB.

"As noted to beta customers, if [they] are running Vista SP1 beta software, as part of the beta programme, Office 2007 SP1 on pre-release Windows Vista SP1 will automatically install as planned for this beta programme," said Bobbie Harder, a senior program manager with the WSUS (Windows Server Update Services) group.

Others, including Susan Bradley, a writer for the WindowsSecrets newsletter, noticed the automatic download and install of Office 2007 SP1. "I woke up on Wednesday morning to find a notification that a Vista machine had rebooted after being patched," Bradley said in Thursday's issue of the newsletter. "I found, to my surprise, that the new Service Pack 1 for Office 2007, which was released on Tuesday, had been auto-installed."

Bradley also said that even if users of Vista SP1, Windows XP SP3 or WSUS 3.0 SP3 manually installed Office 2007 SP1, Automatic Updates later automatically installs - actually re-installs - the service pack.

Earlier this week, when Microsoft unveiled the service pack, it said Automatic Updates (AU) would not be used to deliver Office 2007 SP1 for at least three months, and maybe as many as six months. In any case, it promised to give users 30 days' notice before it pushed it out using AU.

While technically true - Office 2007 SP1 is only shoved to users running a preview OS - some Vista users have been confused by the appearance of the service pack in their Windows Update listings this week as they downloaded and applied numerous security patches.

Harder explained what Vista users experience in a blog post on Thursday. "On Vista in the Windows Update Control Panel Applet, the Office 2007 SP1 will appear as an available update to download and install, but it will NOT automatically download and install, regardless of the automatic settings," she said.

That's true, countered Bradley, but because the service pack shows on the list and is checked by default, it's easy for users to overlook it, then get slammed with the massive download. "If you are a bit asleep and just blindly approve all of the patches, you get a very large wait while SP1 for Office 2007 is downloaded," she said.

A reader of PC Advisor's sister title Computerworld US reported exactly that. "I received [Office 2007 SP1] last night Dec 11 as part of Windows Auto-update," said someone identified as 6monthVistaUser in a comment attached to a story about SP1. "Last night was the largest auto-update ever (230 MB download) filled with 11 updates. 1 was for IE v7, 6 were for Vista cumulative patches, 1 was the Office 2007 Service Pack 1, the other one was for Business Contacts Manager SP 1."

Harder defended the process. "For customers who want the benefits of Office 2007 SP1 now, we have made it available," she said. She also noted that users could choose not to pull in the service pack. "Download and installation of the Office 2007 SP1 via the Vista Windows Update control panel applet requires explicit user interaction, just as with the Microsoft Update site," she said. "Once the list of available updates appears, they can de-select or uncheck the box next to Office 2007 SP1 and choose to download and install other updates, or just close the applet."

The next time Windows Update runs, however, Office 2007 SP1 reappears, again checked by default. To strike it off the list, users must right-click the item in the list and choose "hide update".

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