FAQ: How to dump Vista SP1

Computerworld - Last week Microsoft rolled out Windows Vista Service Pack 1 (SP1) to Windows Update, giving the majority of users their first look at the big update. Some didn't like what they saw.

At all.

One user, identified as "ronroyer" in a comment posted to the Vista blog, said SP1 had crippled his connection to the Internet. "I tried everything ... completely useless ... this has been nothing but one frustrating experience," said ronroyer.

If you've had problems with SP1 -- and by the tone of much of the news coverage, you're not alone -- you can turn back the hands of time, or at least those on your PC, to before you jumped on the service pack.

Here's the skinny, as we know it now.

How do I get rid of Service Pack 1? (SP1) The simplest way, according to Microsoft's own documentation and its support staff, is to uninstall it using the normal procedure for tossing out unwanted applications.

From Control Panel, click "Programs" then in the ensuing window under "Programs and Features," click "Uninstall a program."

Click "View installed updates," select "Service Pack for Microsoft Windows (KB936330)" and click "Uninstall."

How long does it take to uninstall SP1? According to a Microsoft technical support representative we talked to, it should take between 20 and 30 minutes to uninstall the service pack. A Computerworld guinea pig PC, loaded with Vista Ultimate and updated last week to SP1, took around 35 minutes to return to its pre-updated self.

Like the installation of SP1, the uninstall is a three-stage process. There is one reboot in the middle, then another nearer the end. The in-the-middle restart doesn't happen automatically, however, so you have to stick around to click a button. The rest is hands-off.

Are there any SP1 bits left on the machine? Microsoft says no. But the updates which Microsoft required prior to offering Service Pack 1 through Windows Update -- dubbed "prerequisites" by the company -- do remain.

These include the January KB935509 update to BitLocker, and two others originally delivered in February, KB937287 and KB938371. The middle update of trio, KB937287, remember, was the one which raised a ruckus last month when some users reported that it had sent their PCs into a death spiral of endless reboots. Microsoft yanked the update several days later the automatic delivery list; users were still required to download and install it last week, however, before they were able to "see" SP1 on Windows Update.

Are there any other Microsoft-approved ways to uninstall SP1? According to the KB948537 support document, the company also says users can roll back to a pre-SP1 state by using Vista's System Restore feature.

Microsoft spells out two options: One "offline" -- if the PC isn't connected to the Internet, or perhaps because of SP1 not able to -- and another dubbed "online." The former requires that you have your original Vista install DVD and a PC that will boot from the optical drive.

For more details, KB948537, which is available here, spells out the steps for each restore option.