The Internet is littered with stories about the soon to be released third service pack for Windows XP. Here's an uncommon wrinkle. Don't install it when it's officially released on the 29th. Not yet, it's too soon.
I say this at the risk of not being a team player. Fellow CNET blogger, Robert Vamosi, recently wrote "Starting April 29, all Windows XP SP2 users should upgrade to SP3..." If this is my last posting, you'll know why.
A fundamental tenant of Defensive Computing is not to install newly released software. With Windows XP SP3, the reason to wait is software incompatibilities. Even though SP3 has underdone much testing, it's a big world and there are bound to be problems with some software. By waiting, you let everyone else find and fix the problems before you face them.
If you are using software that's impacted adversely by SP3, you don't want to be among the first people to call the software vendor for help. It's far better to call a couple months later when the problem and the solution are well known and grooved in.
Deciding when to install new software involves balancing the risk vs. the reward. While the risk with SP3 should be small, so too is the reward. In fact, the reward is pert near zero for anyone who is up to date on Windows bug fixes. Granted, this is one person's opinion, and reasonable people may disagree, but from what I've read, the new features added to XP by the third service pack are a big yawn.
The suggestion to wait on installing SP3 is not based on specific problems, issues or incompatibilities. That said, it's not hard to find them.
Just today, ComputerWorld noted that Mac users need new versions of Apple's Boot Camp and VMware's Fusion to be compatible with XP SP3. On The Personal Computer Show this week, the host, Joe King, told of problems using a Trend Micro anti-malware suite of software with SP3. If you go to TrendMicro.com and search for Windows XP SP3, there's nothing there about compatibility issues with the new service pack. It's too soon.
How long to wait? I'd give SP3 at least a couple months, maybe three or four.
When the time comes to install SP3, the right approach is to first make a disk image backup of the partition containing Windows. Anything else is risky. No doubt SP3 was designed to be un-installed should the need arise, but putting your full faith in this would be a mistake.
Also, the installation process is going to exercise the heck out of the file system, so I suggest first running a thorough Check Disk. If you have any other hard disk diagnostic utilities, it would be good to insure the hard disk is healthy before installing the service pack. And a defrag can't hurt. At the very least, make a restore point.
Update. April 30, 2008: I told you so. On April 29th, Ina Fried wrote that Windows XP SP3 has been delayed to a newly discovered software incompatibility. See XP update delayed over glitch. As XP SP3 gets distributed to more and more people, we can expect still more software incompatibilities to surface.
Update. May 9, 2008: From ComputerWorld: XP SP3 cripples some PCs with endless reboots. One of the problems described in this article is a mistake by HP - running software meant for Intel processors on computers running AMD processors. Normally, this is not a problem, but for some reason it causes a problem after installing XP SP3.
Update. May 9, 2008: FYI: From the Microsoft Knowledge Base How to remove Windows XP Service Pack 3 from your computer.
Update. May 22, 2008: FYI: XP SP3 triggers false positives in security apps by Scott Dunn.
Update. July 23, 2008: After taking my own advice for three months, I installed SP3 on a guinea pig machine and it broke Windows Update. The next day, on a different computer, the same thing happened. See Post-SP3 patch breaks Windows Update.