Installing Devices on 64-Bit Systems

If your device will be installed on both 32-bit platforms and 64-bit platforms, you must use the following steps when creating a driver package:

• Provide both 32-bit and 64-bit compilations of all kernel-mode drivers, device installation applications, device installers, class installers, and co-installers. For more information, see Porting Your Driver to 64-Bit Windows.
• Provide one or more cross-platform INF files that use decorated INF sections to control platform-specific installation behavior.

If you are writing a device installation application, the 32-bit version must be the default version. That is, the 32-bit version should be invoked by Autorun (described in the Platform SDK documentation), so that it starts automatically when a user inserts your distribution disk.

The 32-bit version of the application must check the value returned by UpdateDriverForPlugAndPlayDevices. If the return value is ERROR_IN_WOW64, the 32-bit application is executing on a 64-bit platform and cannot update "in-box" drivers. Instead, it must call CreateProcess (described in the Platform SDK documentation) to start the 64-bit version of the application. The 64-bit version can then call UpdateDriverForPlugAndPlayDevices, specifying a FullInfPath parameter that identifies the location of the 64-bit versions of all files.