C++ read data of a registry key value

Question

I am trying to get the data of a registry key value, but then I encountered this error,
[bcc64 Error] AAP.h(210): invalid operands to binary expression ('const wchar_t *' and 'const wchar_t *') (also on this screenshot)

I'm pretty sure I did something wrong, or didn't do properly, (I'm new to c++)

HKEY currentKey;
TCHAR name[256];
String loly;
void fivenum()
{
    DWORD dwSize = 1024;
    DWORD dwIdx = 0;
    long result = 0;
    long fivenumberresult = 0;
    result = RegOpenKeyEx(HKEY_CURRENT_USER, _T("Software\\Microsoft"), 0, KEY_ENUMERATE_SUB_KEYS | KEY_QUERY_VALUE | KEY_SET_VALUE, &currentKey);
    if(result != ERROR_SUCCESS)
    {
       // fail
    }
    else
    {
       DWORD indexs = 0;
       fivenumberresult = RegEnumKeyEx(currentKey, indexs, name, &dwSize, NULL, NULL, NULL, NULL);
       if(!fivenumberresult)
       {

        std::wstringstream box_message;
        loly = box_message.str().c_str();
       }
    }
}

String awit;
void reg4()
{

    HKEY hKey = 0;
    wchar_t buf[255];
    DWORD dwBufSize = sizeof(buf);
    awit = _D("");

    const wchar_t* xds = loly.w_str();
    const wchar_t* xd = L"Software\\Microsoft\\" + xds;
    if( RegOpenKeyExW(HKEY_CURRENT_USER,xd,0,KEY_QUERY_VALUE,&hKey) == ERROR_SUCCESS)
    {

       if(RegQueryValueExW(hKey,L"14770",0, 0, (BYTE*)buf, &dwBufSize) == ERROR_SUCCESS)
       {
          std::wstringstream box_messagess;
          for(DWORD i = 0; i < dwBufSize; ++i)
          {
                box_messagess << IntToHex(static_cast<int>(buf[i]), 2).c_str() << _D(",");
          }
          awit = box_messagess.str().c_str();

       }

    }
}