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PC Hacks
By Jim Aspinwall
October 2004
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Please Continue Anyway

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Figure 1. Windows Logo certification warning dialog

To solve this problem, locate and download a Windows-certified driver from the vendor's web site, assuming one is available. The risk of not doing so is minimal, but using a certified driver removes an element of potential surprise and disaster that may appear later on. Certified drivers will often be flagged with the words "WHQL Certified," as shown in Figure 2.

Figure 2. nVidia's driver feature web page listing WHQL certification

The warning dialog appears because the driver installation package did not come with a digital certificate that matches the one in Windows to let the installation process know the file was tested by a Microsoft-approved lab.

The intention is good: vendors have someone who knows the Windows environment very well review their drivers to ensure they are not consuming all the memory, stealing resources, or overwriting operating system files or other applications' files, and then they assure the public that things are OK. Then the vendor can deliver the assurance that all is well with the program or driver in the form of a digital certificate that matches the one Microsoft provided in the operating system. This is Microsoft's answer to the many cases of driver and program conflicts we all faced under Windows 95 and 98, when the Windows market was still relatively young and programmers ran wild trying to get cool new products into users' hands.

The scare tactic has some legitimate basis, especially if you're Microsoft and want hundreds of vendors to spend thousands of dollars on week-long visits to testing labs to get their wares certified as "not harmful to Windows." However, most companies can barely afford to do some of this Windows compliance testing in their own labs, much less risk the time and money sending their products to a distant lab hoping everything will pass with flying colors. Most products do not pass Windows Logo certification the first time and may not pass at all by the strict rules of the program. Passing the certification often requires the developer to plead their case and show the testing lab how their product really does comply with sound Windows programming and operation, despite Microsoft's rules and limitations, and ultimately get an approval by conditional and careful exemption.


Microsoft certifications or compliance with their Authenticode program are intended to ensure applications or drivers are secure by protecting the files against tampering. However, the lack of these stamps of approval does not necessarily mean that the application or driver might carry a virus, is carelessly written, or is otherwise harmful; but it also means that no one but the original vendor or their developer has reviewed and tested them.

If you have a choice, locate, download, and install certified drivers. If you do not, be prepared to remove the driver and device, and possibly even boot into Safe Mode or use System Restore to extract the offending code.

You can access System Restore through StartAll ProgramsAccessoriesSystem Tools.

Today programmers have to try really hard to screw up Windows XP and Windows Server 2003—and certainly some of them do—but a clear majority of them, especially easily recognized brand name vendors, do not. Microsoft is a little better about documenting the tools and resources developers use, and developers are more mature and their employers are much more concerned about excessive support costs and product returns than making a quick buck.

You may see the compatibility testing warning dialog during one or two of approximately 20 installations of new hardware or programs, and only in one or two out of 100 cases will there ever be a problem. Fortunately, when you continue the installation, Windows Me and XP create a System Restore Point, saving the current, working preinstallation configuration that you can go back to if something does not work correctly. If your new hardware or software is from a reputable source, go ahead and select Continue Anyway: you have Windows System Restore and likely the vendor to help get you back to good working condition.

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