diff --git a/dlls/setupapi/devinst.c b/dlls/setupapi/devinst.c
index ef56d2be300..966af759606 100644
--- a/dlls/setupapi/devinst.c
+++ b/dlls/setupapi/devinst.c
@@ -3647,6 +3647,20 @@ BOOL WINAPI SetupDiSetClassInstallParamsA(
     return FALSE;
 }
 
+/***********************************************************************
+ *		SetupDiSetClassInstallParamsW (SETUPAPI.@)
+ */
+BOOL WINAPI SetupDiSetClassInstallParamsW(
+       HDEVINFO  DeviceInfoSet,
+       PSP_DEVINFO_DATA DeviceInfoData,
+       PSP_CLASSINSTALL_HEADER ClassInstallParams,
+       DWORD ClassInstallParamsSize)
+{
+    FIXME("%p %p %x %u\n",DeviceInfoSet, DeviceInfoData,
+          ClassInstallParams->InstallFunction, ClassInstallParamsSize);
+    return FALSE;
+}
+
 /***********************************************************************
  *		SetupDiCallClassInstaller (SETUPAPI.@)
  */
diff --git a/dlls/setupapi/setupapi.spec b/dlls/setupapi/setupapi.spec
index a8ce41a5935..48ab1e484f2 100644
--- a/dlls/setupapi/setupapi.spec
+++ b/dlls/setupapi/setupapi.spec
@@ -384,7 +384,7 @@
 @ stub SetupDiSelectDevice
 @ stub SetupDiSelectOEMDrv
 @ stdcall SetupDiSetClassInstallParamsA(ptr ptr ptr long)
-@ stub SetupDiSetClassInstallParamsW
+@ stdcall SetupDiSetClassInstallParamsW(ptr ptr ptr long)
 @ stdcall SetupDiSetDeviceInstallParamsA(ptr ptr ptr)
 @ stub SetupDiSetDeviceInstallParamsW
 @ stdcall SetupDiSetDeviceRegistryPropertyA(ptr ptr long ptr ptr)