Unhandled Exception in vc++ - HRESULT failed

Question

I know the VC++6.0 is very old language, but i don't have a choice, i am just maintaining an existing program, and i encounter this error

Unhandled exception in Assess.exe (KERNELBASE.DLL): 0xE06D7363: Microsoft C++ Exception

And here is my code

 HRESULT hr = CoInitialize(NULL);

// Create the interface pointer.
IModulePtr pI(__uuidof(RPTAModuleInterface)); //the error is here

After debugging and using f11 the program goes to COMIP.H and here is the code

explicit _com_ptr_t(const CLSID& clsid, IUnknown* pOuter = NULL, DWORD dwClsContext = CLSCTX_ALL) throw(_com_error)
    : m_pInterface(NULL)
{
    HRESULT hr = CreateInstance(clsid, pOuter, dwClsContext); 
    //the program goes to CreateInstance Method

    if (FAILED(hr) && (hr != E_NOINTERFACE)) {
        _com_issue_error(hr); 
        //the program goes here and show the error msg
    }
}

And Here is the CreateInstance

HRESULT CreateInstance(const CLSID& rclsid, IUnknown* pOuter = NULL, DWORD dwClsContext = CLSCTX_ALL) throw()
{
    HRESULT hr;

    _Release();

    if (dwClsContext & (CLSCTX_LOCAL_SERVER | CLSCTX_REMOTE_SERVER)) {
        IUnknown* pIUnknown;

        hr = CoCreateInstance(rclsid, pOuter, dwClsContext, __uuidof(IUnknown), reinterpret_cast<void**>(&pIUnknown));

        if (FAILED(hr)) { 
           // the program goes here and return the hr
            return hr;
        }

        hr = OleRun(pIUnknown);

        if (SUCCEEDED(hr)) {
            hr = pIUnknown->QueryInterface(GetIID(), reinterpret_cast<void**>(&m_pInterface));
        }

        pIUnknown->Release();
    }
    else {
        hr = CoCreateInstance(rclsid, pOuter, dwClsContext, GetIID(), reinterpret_cast<void**>(&m_pInterface));
    }

    return hr;
}

I don't know what's the error here, this is header file and i think there's no error here. Any Idea how to fix this thing?

Updated

in my RPTAInterface.tlh i saw the declaration of RPTAModuleInterface

struct /* coclass */ RPTAModuleInterface;

struct __declspec(uuid("d6134a6a-a08e-36ab-a4c0-c03c35aad201"))
RPTAModuleInterface;

Answer 1

_com_issue_error() throws a _com_error exception that you are not catching. You need to wrap your code in a try/catch, eg:

try
{
    IModulePtr pI(__uuidof(RPTAModuleInterface));
    // ... 
}
catch(const _com_error& e)
{
    // e.Error() will return the HRESULT value
    // ...
}

Clearly CoCreateInstance() is failing. There is likely no library installed on the machine that registers the CoClass for RPTAModuleInterface, so it cannot be created. But you will have to look at the actual HRESULT to be sure why CoCreateInstance() is failing.