jump to navigation

Background on Driver Installation in MDT November 2, 2009

Posted by keithga in MDT 2010.

Most Drivers are installed via an *.inf file. These *.inf files contain all the meta-data needed to define what a driver does, what devices it’s used for, and how it’s installed, including files, registry keys, and any other custom action(s).

When a new hardware device is added to the system, Windows will detect the device and gather as much information about it as possible. This includes a list of Plug and Play Device ID’s (PnPID’s) that are unique to that make and model of device. For example:


An *.inf file in turn will contain a list of Plug and Play devices its compatible with.


When presented with a list of Devices, and a collection of drivers, the OS will find all combinations that match, and determine which one is the best (most descriptive) match.

What’s cool about MDT is if you have more than one possible match, the MDT system will copy all possible matches to the OS. Windows has Driver Ranking Algorithms that will determine the best possible match given a set of possible matches.

It can be important, therefore, to insure that you keep your MDT Driver store clear of all duplicates.

Driver Install Packages

Most hardware manufacturers will produce a driver in two parts:

  • A basic driver package, Containing an *.inf file describing the package, a *.sys file containing any driver code, and a *.cat digital signature. The digital signature indicates that the driver has gone through some basic testing, what it’s origin is, and that it has not been tampered with. This driver package could be copied to Windows Update or the Windows Update Catalog, and is typically the kind of driver package that is best when importing drivers into MDT 2010 workbench.
  • In addition, a company may wish to include add-ons: Tools, Utilities, or Setup wrappers for end-users to install the drivers from the *.inf package more easily. An example might be an advanced radio tuning tool included with a Wi-Fi Driver, or perhaps a Video Communications sample included with a Web-Cam driver. These packages are typically optional, however sometimes they may be required.

When searching for a basic driver *.inf package, typically the best place to start is looking *within* an *.exe Driver Install Package. I like to use 7-Zip to search within self extracting *.exe files for *.inf files.

MDT Drivers

MDT was designed to handle the OS relationship between Devices and Drivers. In other systems, you might assign a driver package to a specific Make and Model. However, whenever a new system comes out, you need to re-define the relationship between the drivers and the Make and Models. Say you have the drivers defined for the Dell D620, and you need to add support for the Dell D820. These two machines mostly share the same class of components, with the same PnP ID’s. With the Driver system in MDT, the drivers are not associated with the Make/Model, instead they are associated with the PnPID of the device itself. All the components of the Dell D620 will automatically be used in the D820, if they share the same PnPID (same device), which in this case they mostly do.



Keith Garner is a Deployment Specialist with Xtreme Consulting Group


1. yoke88 - July 19, 2010

Hello,Keith ,where do you find common drivers? and what was the size of your mdt drivers folder?

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out /  Change )

Google+ photo

You are commenting using your Google+ account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )


Connecting to %s

%d bloggers like this: