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Red Software Systems - software engineering consultancy
Red Software Systems - software engineering consultancy

Windows Logo Testing

Independent Hardware Vendors (IHVs) looking to get their PC-connected products ‘Certified for Windows’ need to test their hardware and drivers using the WHQL (Windows Hardware Quality Labs) test programs. Microsoft provides resources for developers; follow this link to their WHQL getting started page.

Since 2007 the Windows Logo Kit (WLK) must be used for all new Windows logo submissions. Testing with the WLK requires the use of a dedicated laboratory network of PCs to run the test programs. The network consists of a Driver Test Manager (DTM) Controller running Windows Server, one or more DTM Client machines which perform the actual device testing, and one or more machines running DTM Studio where the tests are scheduled and the results are displayed.

x64 Windows is here now

More and more home and business users are harnessing the power of their new machines and upgrading to x64 Windows 7. From Windows Vista x64 and onwards, Microsoft will no longer allow a device to be installed under Windows without a digital certificate. Indeed, at present they will not grant a digital certificate for 32-bit Windows unless the device and driver has passed all the same WLK tests for x64 Windows. IHVs who previously opted not to do WHQL testing and to live with the install-time warning dialogs will soon be forced into running these tests on their devices and drivers.

WLK/DTM Complexity

The WLK/DTM system is a large complex application that requires a high level of technical comptence to install and operate effectively. There are also idiosyncrasies with the individual tests. Due to the large volume of customer support incidents, Microsoft have withdrawn free WLK support and replaced it with a premium service.

Red has an on-site WLK/DTM test laboratory set up and ready for IHV device testing. We have successfully run a number of our customer’s products through the prescribed tests. We can take your device and driver, run the necessary tests and compile a detailed report on any problems found. We can also run the whole Winqual qualification process of submitting packages and interacting with Microsoft if required. If you make you driver code available to us, we can isolate any driver problems by running the tests under the Windows debugger. If you want we can even fix any driver problems we find.

Driver Reliability

When a device requires a Windows driver, the DTM system will schedule a series of driver reliability tests. These tests stress the driver and associated device over a range of potential operational scenarios. The tests are designed to expose common problems in drivers that may lead to system unreliability. IHV's devices that pass these DTM driver reliability tests can be sure that their device is not causing their customer's OS reliability problems. This is where the dreaded blue screen crash is caught and exposed.

Bus Specification Conformance

If your product connects to the PC using a bus technology or standard protocol, the DTM will schedule programs that test the device’s conformance to the bus or protocol specification. These tests normally bypass the driver and use the relevant bus driver to exercise the device directly, thereby testing the device’s firmware implementation of the standard bus protocol.

Red have bus protocol analyzers for USB and Firewire and are experts in these protocols. We can provide analyzer traces in conjunction with any test failures, pinpointing the code responsible. Give us your firmware code and we can make recommendations for improvements, or even make the fixes for you.

Function Specific Testing

The DTM will also schedule function specific tests for the device. The programs test how the device and driver interact with the operating system services for the particular class of device. For example, there are printer specific and smart card specific tests. These tests are designed to isolate any application-layer problems with the device and ensure that the device operates properly across a broad range of application scenarios.

Benefits of Logo Testing

If you want your device to work with x64 versions of Windows then you must do the logo testing. For x86 Windows, you'll get rid of that nasty dialog that pops up at hardware installation-time. But there are many more reasons to perform theses tests on your devices. There's a reason for all this testing. Microsoft wants to 'enhance the user experience' by making sure that its operating systems work smoothly with any hardware. Even if you don’t want to go through the pain of WHQL submission to get the logo, your customers will benefit from you having run these tests. You might find that intermittent blue screen your customers are reporting is 100% repeatable with the logo tests.

You'd be surprised at how little all this can cost.  We offer a special fixed rate for Unclassified Signature testing of just £500 per Operating System.  Letting Red take on the burden of your Windows logo testing will save you time and money. Our DTM laboratory is set-up and ready to go. We have the relevant experience in driver development and have solved all of the common driver problems. We can help you with your bus and protocol standards compliance. We’ll provide you with detailed tests reports and help you isolate and solve those problems quickly and effectively. Don’t take the risk running around in circles for weeks on end chasing problems, drop us a line.


Phone - +44 (0)20 8341 7629 Email - enquiries@redsoftsys.com