Exception when creating ADO Command object at end of Application - com

Question

I'm now moving a big software from OWL to MFC, most of the mission has been done, but I face alot of problems like this one when the application is closing this exception arises
When I clicked break the debuger lead me to this
that was the call stack
msdart.dll!_UMSEnterCSWraper() Unknown
msado15.dll!ATL::AtlModuleGetClassObject(struct ATL::_ATL_MODULE *,struct _GUID const &,struct _GUID const &,void * *) Unknown
msado15.dll!ATL::CComModule::GetClassObject(struct _GUID const &,struct _GUID const &,void * *) Unknown
msado15.dll!_DllGetClassObject#12() Unknown
ole32.dll!CClassCache::CDllPathEntry::DllGetClassObject(const _GUID & rclsid, const _GUID & riid, IUnknown * * ppUnk, int fMakeValid) Line 3317 C++
ole32.dll!CClassCache::CDllFnPtrMoniker::BindToObject(const _GUID & riid, void * * ppvResult) C++
ole32.dll!CClassCache::SearchForLoadedClass(const ACTIVATION_PROPERTIES & ap, CClassCache::CDllClassEntry * * ppDCE) C++
ole32.dll!ICoCreateInstanceEx(const _GUID & Clsid, IUnknown * punkOuter, unsigned long dwClsCtx, _COSERVERINFO * pServerInfo, unsigned long dwCount, unsigned long dwActvFlags, tagMULTI_QI * pResults, ActivationPropertiesIn * pActIn) Line 1163 C++
ole32.dll!CComActivator::DoCreateInstance(const _GUID & Clsid, IUnknown * punkOuter, unsigned long dwClsCtx, _COSERVERINFO * pServerInfo, unsigned long dwCount, tagMULTI_QI * pResults, ActivationPropertiesIn * pActIn) Line 332 C++
ole32.dll!CoCreateInstanceEx(const _GUID & Clsid, IUnknown * punkOuter, unsigned long dwClsCtx, _COSERVERINFO * pServerInfo, unsigned long dwCount, tagMULTI_QI * pResults) Line 157 C++
ole32.dll!CoCreateInstance(const _GUID & rclsid, IUnknown * pUnkOuter, unsigned long dwContext, const _GUID & riid, void * * ppv) Line 110 C++
> DBCore.dll!_com_ptr_t<_com_IIID<ADODB::_Command,&_GUID_b08400bd_f9d1_4d02_b856_71d5dba123e9> >::CreateInstance(const _GUID & rclsid, IUnknown * pOuter, unsigned long dwClsContext) Line 586 C++
DBCore.dll!TADOCommand::Init(TADOConnection * connection) Line 32 C++
DBCore.dll!TADOCommand::TADOCommand(TADOConnection * connection) Line 8 C++
AmnDbase.dll!TQuery::Init() Line 335 C++
AmnDbase.dll!TQuery::TQuery(const TDatabase * db, TTable * Tbl) Line 304 C++
AmnDbase.dll!TDirectQuery::TDirectQuery(const TDatabase * db) Line 932 C++
AmnDbase.dll!CommitUnsavedTransactions(TDatabase * db) Line 674 C++
AmnDbase.dll!TDatabase::Disconnect() Line 427 C++
AmnDbase.dll!TDatabase::CloseDb() Line 455 C++
AmnDbase.dll!TDatabase::Close() Line 417 C++
AmnLib2.dll!TStoreFile::Close() Line 3275 C++
AmnLib2.dll!TStoreFile::~TStoreFile() Line 1040 C++
AmnLib2.dll!`GetStoreFile'::`2'::`dynamic atexit destructor for 'StoreFile''() C++
AmnLib2.dll!_CRT_INIT(void * hDllHandle, unsigned long dwReason, void * lpreserved) Line 415 C
AmnLib2.dll!__DllMainCRTStartup(void * hDllHandle, unsigned long dwReason, void * lpreserved) Line 526 C
AmnLib2.dll!_DllMainCRTStartup(void * hDllHandle, unsigned long dwReason, void * lpreserved) Line 476 C
this is the code that called the CreateInstance
/// Init the command instance.
void TADOCommand::Init( TADOConnection* connection)
{
m_CmdText = "";
m_nRecordsAffected = 0;
m_Command = NULL;
m_ResultSet = NULL;
m_CmdConnection = NULL;
m_CmdRecordset = NULL;
if( connection->IsNull())
return;
m_Command.CreateInstance( __uuidof( Command));
SetConnection( connection);
SetCommandTimeOut( connection->GetCommandTimeout());
}
I want the code to stay working without changing any code especialy in the database layer is this due to call of couninitialize from MFC?? how can I detect that or solve this issue?
and the m_Command was defined as
_CommandPtr m_Command;
and it is com interface first it is set to null then call CreateInstance it works fine each time unless the last time it fails with this exception

Answer 1

The code seams to be executed when your DLL is unloaded or loaded, as far as I can see in the callstack.
When this is "loading code" the question arrises: Why is the LDL loaded again.
But using COM in DllMain is no good at all. See here
COM should never be used inside a DllMain code.
I suppose that your DLL is unloaded after the MFC already called CoUninitialize. Or your DLL is reloaded by some code, that shouldn't be executed in the shut down of your application.