ACM Installation

We are having problems installing ACM audio codecs on XP PCs.

We have a .reg file which sets up Drivers32 and drivers.dec. This works on
some PCs but not others.

When it doesn't work the correct entries (I think) end up in the registry
but neither control panel or any applications can see the codecs.

..reg file

Windows Registry Editor Version 5.00

[HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows
NT\CurrentVersion\drivers.desc]
"niceaca.acm"="NICE ACA Audio Codec"
"acelp.acm"="NICE ACELP Audio Codec"
"nicadpcm.acm"="NICE ADPCM Audio Codec"
"apcoP25.acm"="NICE IMBE Codec"
"g723.acm"="NICE G723 Audio Codec"
"g728.acm"="NICE G728 Audio Codec"
"g729a.acm"="NICE G729a Audio Codec"
"Gain.acm"="NICE Gain Filter"
"Speed.acm"="NICE Speed Filter"

[HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows NT\CurrentVersion\Drivers32]
"msacm.niceaca"="niceaca.acm"
"msacm.niceacelp"="acelp.acm"
"msacm.niceadpcm"="nicadpcm.acm"
"msacm.niceimbe"="apcoP25.acm"
"msacm.niceg723"="g723.acm"
"msacm.niceg728"="g728.acm"
"msacm.niceg729a"="g729a.acm"
"msacm.nicegain"="Gain.acm"
"msacm.nicespeed"="Speed.acm"

The .acm files are copied into System32.