Driver Signing, sometimes referred to as a digital certification or WHQL, is Microsoft®'s method of approving device drivers for the Windows® XP operating system.
The 'In-Box' drivers already supplied with the Windows® XP have been tested and approved by Microsoft® and if the appropriate Brother driver is included with the Windows® XP operating system, then it is already digitally signed. Because of the convenience of installation using in-box drivers, we generally recommend that you use them.
However, to address the extra software functionality that an in-box driver is not able to offer, Brother is developing new drivers that will allow access to Brother's special features. These new printer drivers - known as native drivers - must be tested, this testing process is referred to as 'Driver Singing'.
When a new driver has been tested and is found to cause no problems with the stability of the Windows® XP operating system, the driver is issued with a digital signature which Brother then attaches to the actual driver download file. When a digitally signed driver is installed into Windows® XP, the driver installs into the XP operating system without any warning messages.