How can I give an old ActiveX control new GUIDs? - c++

Question

I am trying to modify an ActiveX control developed in Visual Studio 2008 to use it for a purpose for which it was not originally designed. I will be reusing at least 90% of its code. Therefore, I would like to begin by creating an identical control that uses different GUIDs. I tried to follow instructions I found here (a very old link, written in 2004), but when I tried to build my project, I got an assertion failure in ctlreg.cpp line 113. Then, I restored all my changed files back to their original states, and for each GUID is the .odl file, I searched for the GUID in my .cpp and .h files and changed it wherever I found it. I also made sure to change my major version number. I still get the assertion failure. What else should I be doing?
Here's the code from ctlreg.cpp from the start of the method containing the assertion to the assertion itself:
BOOL AFXAPI AfxOleRegisterTypeLib(HINSTANCE hInstance, REFGUID tlid,
LPCTSTR pszFileName, LPCTSTR pszHelpDir)
{
BOOL bSuccess = FALSE;
CStringW strPathNameW;
wchar_t *szPathNameW = strPathNameW.GetBuffer(_MAX_PATH);
::GetModuleFileNameW(hInstance, szPathNameW, _MAX_PATH);
strPathNameW.ReleaseBuffer();
LPTYPELIB ptlib = NULL;
// If a filename was specified, replace final component of path with it.
if (pszFileName != NULL)
{
int iBackslash = strPathNameW.ReverseFind('\\');
if (iBackslash != -1)
strPathNameW = strPathNameW.Left(iBackslash+1);
strPathNameW += pszFileName;
}
if (SUCCEEDED(LoadTypeLib(strPathNameW.GetString(), &ptlib)))
{
ASSERT_POINTER(ptlib, ITypeLib);
LPTLIBATTR pAttr;
GUID tlidActual = GUID_NULL;
if (SUCCEEDED(ptlib->GetLibAttr(&pAttr)))
{
ASSERT_POINTER(pAttr, TLIBATTR);
tlidActual = pAttr->guid;
ptlib->ReleaseTLibAttr(pAttr);
}
// Check that the guid of the loaded type library matches
// the tlid parameter.
ASSERT(IsEqualGUID(tlid, tlidActual));