Windows Hardware Quality Labs (abbreviated as WHQL) is a Microsoft testing operation. WHQL is planned to show to Microsoft, and ultimately to the customer (that’s you!), that certain hardware or software item will work adequately with Windows.
When a piece of hardware or software has passed Windows Hardware Quality Labs, the manufacturer can use a “Certified for Windows” logo (or something similar) on their product packaging and be publicizing. A logo is used so that you can plainly see that the product has been tested to merits set by Microsoft, and is therefore suited with whatever version of Windows you’re running. Products that have the Windows Hardware Quality Labs logo are included in the Windows Hardware Compatibility List.
In addition to hardware and software, device drivers also usually tested and Windows Hardware Quality Labs certified by Microsoft. You’ll probably encounter the WHQL term most frequent when you’re working with drivers. If a driver hasn’t been WHQL certified you can still install it, but a warning message will tell you about the driver’s lack of certification before the installation. WHQL certified drivers don’t show a message at all.
A WHQL warning may read something like “The software you are installing has not passed Windows Logo testing to check its compatibility with Windows” or “Windows can’t verify the publisher of this driver software”.
Dissimilar versions of Windows deal this a bit differently.
Unsigned drivers in Windows XP always follow this rule, meaning a warning will show if the driver hasn’t passed Microsoft’s Windows Hardware Quality Labs.
Windows Vista and newer versions of Windows also follow this order, but with one exception: they don’t show a warning message if the company signs their own driver. In other words, no warning will show even if the driver hasn’t gone through Windows Hardware Quality Labs, so long as the company issuing the driver has added a digital signature, verifying its origin and legitimacy.
In a condition like that, even though you won’t see a cautioning, the driver wouldn’t be competent to use a “Certified for Windows” logo or mention that on their download page, because that WHQL certification hasn’t happened.
How to find and Install WHQL Drivers:
Some WHQL drivers accommodated through Windows Update, but surely not all of them. You can stay up to date on the latest WHQL driver releases from major manufacturers like NVIDIA drivers, ASUS, and others on our Windows 10 Drivers, Windows 8 Drivers, and Windows 7 Drivers pages. Free driver updating tools like Driver Booster can be set up to only show you updates for drivers that have passed WHQL tests. See How to Update Drivers for more information on installing drivers.
Not all drivers and hardware are going to run via WHQL. This just means that Microsoft can’t be positive that it will work with their operating system, not that it for sure won’t work at all. In general, if you know you’re downloading a driver from the hardware maker’s legitimate website or download source, you can be logically confident that it’ll work if they state that it does so in your version of Windows. Most companies issue beta drivers to testers prior to WHQL certifications or in-house digital signing. It means to say that most drivers go through a testing stage that lets the company assuredly tell the user that their drivers will work as expected.
You can learn more about hardware certification, along with the essentialities and procedures to get it going, at Microsoft’s Hardware Device Center.
Windows Hardware Quality Labs testing or WHQL Testing is Microsoft‘s testing method which requires running a series of tests on third-party hardware or software, and then submitting the log files from these tests to Microsoft for review. The process may also add Microsoft running their own tests on a wide range of apparatus. Such as different hardware and different Microsoft Windows editions.