User-mode vs. Kernel-mode Drivers

Applies To: Windows Server 2003 with SP1

Drivers can be written in either user mode (also called version 3 drivers) or kernel mode (also called version 2 drivers). In Windows NT 4.0, drivers were moved into kernel mode to improve performance. However, when a kernel-mode driver fails, it can crash an entire system, whereas the failure of a user-mode driver causes only the current process to crash. Because of this difference, and because performance enhancements were made in Windows 2000 and Windows Server 2003, native drivers on Windows 2000 and later run in user mode. Windows Server 2003 can still run kernel-mode drivers, although this is not recommended for the stability reasons mentioned previously. It is also possible to install kernel-mode drivers using the Additional Drivers option on Windows 2003 print servers to support Windows NT 4.0 clients.

All drivers on the Windows Server 2003 CD are user mode, except those in the printers\nt4\i386 directory, which are kernel mode to support Windows NT 4.0 clients.

To check whether a driver that you have installed is user mode or kernel mode, do the following:

  1. Click Start, and then choose Printers Folder.

  2. Click File, and then click Server Properties.

  3. Click the Drivers tab.

  4. Look at the Version column for a specific driver. If the version indicates Windows NT 4.0 you have a kernel-mode driver. If the version is Windows 2000, Windows XP and Windows Server 2003, you have a user-mode driver.

Note

The Server Properties dialog box contains information and settings about the entire print server.