Program for WM_SETTINGSCHANGE refreshing LogonUI.exe - repost

I'm doing a change by script to the following registry key: "HKLM\SOFTWARE\Microsoft\Windows\CurrentVersion\Authentication\LogonUI\Background\OEMBackground" Now the challenge is to inform "[login to view URL]" about this change. "[login to view URL]" is the logon screen application of "Windows 7". I discovered that the Windows API must be used with a call of WM_SETTINGCHANGE, but I'm not a C++ programmer and would like to have a standalone application which I can call from the command line to perform the change. In Windows XP the following call was available: "[login to view URL] [login to view URL],UpdatePerUserSystemParameters"