All of the files required for the operation or configuration of a device driver are stored in the Windows NT system directory or one of its subdirectories. The various installation methods provide ways to determine the Windows system directory on the local machine. The appropriate locations in which to store the various file types are:
.sys
Copy the driver’s image file into the NT_root\system32\drivers directory.
.dll
Copy the driver’s library files into the NT_root\system32 directory.
.inf
If you distribute an oemsetup.inf (or oemsetnt.inf ) file with your driver, the installation procedure should copy it (renaming it with a unique name) into the NT_root\system32 directory.