Shoutbox

I know this sort of carries on from my last topic, but this problem is unrelated. Promise.

OK, here we go. I haven't yet figured out how to embed the sound data in the .dll, so I am trying to use the registry to find the Msg+ plugins directory, and reference my sound files that way. However, I cannot get the code to open the registry.
Here is the offending code:

code:

---

MPPLUGIN_RETURN_BOOL Initialize(/*[in]*/ DWORD nVersion,
                                /*[in]*/ const char* sUserEmail,
                                /*[in]*/ IDispatch* iMessengerObj)
{
    bool retValue = TRUE;
    long retCode = 0;
    HKEY regKey;
    unsigned long *szType = 0, *szSize = 0;
    unsigned char *szValue = 0;

    retCode = RegOpenKeyEx(HKEY_LOCAL_MACHINE, "SOFTWARE/Patchou/MsgPlus2",
        0, KEY_QUERY_VALUE, &regKey);
    if (retCode != ERROR_SUCCESS)
    {
        MessageBox(NULL, "Error opening registry", "Error", MB_OK);
        retValue = FALSE;
    }
    else
    {
        retCode = RegQueryValueEx(regKey, "PluginDir", NULL,
            szType, szValue, szSize);
        if (retCode != ERROR_SUCCESS){ retValue = FALSE;
            MessageBox(NULL, "Error reading registry", "Error", MB_OK);
        }
        else strcpy(sPluginPath,
            reinterpret_cast<const char*>(szValue));
    }

    retCode = RegCloseKey(regKey);

    if (retCode != ERROR_SUCCESS){ retValue = FALSE;
        MessageBox(NULL, "Error closing registry", "Error", MB_OK);
    }

    return retValue;
}

---

It compiles, it runs, but it doesn't work. The message boxes are to help me (try to) debug.

Any suggestions? All welcome.