LPWSTR value;
HKEY hKey;

long result = RegOpenKeyExW(HKEY_LOCAL_MACHINE, L"RegEntry1", 0, ACCESS|KEY_WOW64_32KEY, &hKey);
if (result == ERROR_SUCCESS)
{
   //WCHAR buffer[512];
   //TCHAR buffer[512];
   LPWSTR buffer[512];
   DWORD bufferSize = sizeof(buffer);
   ULONG queryVal = 0;

   queryVal = RegQueryValueExW(hKey, L"Path", 0, NULL, (LPBYTE)buffer, &bufferSize);
   if (queryVal == ERROR_SUCCESS)
   {
      //Access violation error here; I need some type of conversion.
      value = buffer;
   }
}

WCHAR buffer[512];
DWORD bufferSize = sizeof(buffer);

ULONG queryVal = RegQueryValueExW(hKey, L"Path", 0, NULL, (LPBYTE)buffer, &bufferSize);
if (queryVal == ERROR_SUCCESS)
{
    //...
}

WCHAR buffer[512+1];
DWORD bufferSize = (sizeof(buffer) - sizeof(WCHAR));

LONG queryVal = RegQueryValueExW(hKey, L"Path", 0, NULL, (LPBYTE)buffer, &bufferSize);
if (queryVal == ERROR_SUCCESS)
{
    buffer[bufferSize / sizeof(WCHAR)] = 0;
    //...
}

WCHAR buffer[512+1];
DWORD bufferSize = sizeof(buffer);

LONG queryVal = RegGetValueW(hKey, NULL, L"Path", RRF_RT_REG_SZ | RRF_RT_REG_EXPAND_SZ, NULL, buffer, &bufferSize);
if (queryVal == ERROR_SUCCESS)
{
    //...
}

typedef wchar_t WCHAR;    // wc,   16-bit UNICODE character

typedef __nullterminated WCHAR *NWPSTR, *LPWSTR, *PWSTR;