All multimedia device drivers must be loaded by the Windows 95 device loader MMDEVLDR.VXD, which establishes the device driver(s) in Ring 3, as described previously in this section. All of the sample multimedia INF files have the following line in the section that adds the device to the registry:
HKR,,DevLoader,,mmdevldr.vxd
For example, in the MIDI.INF sample file, such a line is found in both the [MPU401.AddReg] and [ADLIB.addreg] sections. Your INF file must use the same line in the comparable section that adds your device to the registry.