If you keep track of Windows news, you’ve probably heard the controversy over a site that’s offering what they call a “preview pack” of Windows XP Service Pack 3. Microsoft’s Mike Brannigan has already delivered a straightforward recommendation to avoid this package, calling it a “fake” and pointing out that it poses a significant risk to your PC and your data.
I debated whether to include the link to this site and decided not to do so. If you’re bound and determined to screw up your system, then go to thehotfix.net on your own. The proprietors of this site, who are no doubt well-meaning, claim to be doing a service by helping you track down “hard-to-find fixes.” They acknowledge:
This is NOT an official SP3 package from Microsoft, but rather just a collection of hotfixes that will most likely be in SP3 releasing in 2006.
Here’s why this is a bad idea. The reason these hotfixes are generally not available for download from Microsoft’s Web site is that they haven’t been tested for compatibility. They’re intended for use by people who call Microsoft’s support line with a specific issue. If you get one of these hotfixes through the support channel and it causes a problem, you’ve got a support ticket number and you can call back for help in repairing the mess. If you download these hotfixes from an unauthorized site and scramble your system, you’re on your own.
The folks who created this package don’t quite understand the patch development process. Yes, many if not all of these hotfixes will be in SP3, but not in their current form. They’ll be tested and revised and then retested as part of the SP3 package, before it’s released.
Installing a bunch of untested hotfixes on a computer that doesn’t need them is a bad idea. Don’t do it.
Ed Bott 
If, however, it should turn out that you do need one of these fixes, it will effectively be available for free. It appears that Microsoft now clear the funds on your credit card, if you choose to pay rather than use a free support incident [most retail packaged software comes with a couple of free incidents, but check under the support site for that product], but will not actually charge you if the problem was resolved as a bug, which I believe includes providing a workaround rather than a hotfix.
Microsoft do make some hotfixes available through the download site. It depends on the potential impact, the level of testing for the hotfix, the customer demand, and the actual product or component impacted. If a problem has a serious, but not security-related, impact, it may still be placed on the Windows Update web site.