OK Now I understand. Unfortunately dll is still capturing when the error arrise (I didn't call stop function at all) Tomaz Rotovnik

Im so far removed from VB6 that I didn't even consider that you maybe using it.

Anders Molin wrote: That is 4GB, a lot more memory that most computers have... Even if the computer had 8GB of RAM, the memory manager only allows each process 2GB for its address space, or 3GB if the /3GB startup switch were used. Anders Molin wrote: ...if it fails. That should be "when it fails." "When I was born I was so surprised that I didn't talk for a year and a half." - Gracie Allen

First, you work with two diferent instance. Because of that SendMessage doesn't work. Try to know more about instances and exist several approach (InitInstance(), FindWindow() or EnumWindow(), ExitInstance(), Mutex, registry etc).

Thank you Tomaz Rotovnik

getch()

I think I found the problem. I write down steps for those who will have the same problem 1. Because dll which I build is Extension DLL I shouldn't have definition _USRDLL in preprocessor definitions 2. I include CEdit, CString classes which need afxwin.h header so I put #include as first include statement in StdAfx.h header file before all other #include statements. (solved C1189 error) 3. I think CDialog class is MFC so I also set option: Use MFC in a Shared Dll Tomaz Rotovnik

Dear Ryan I tried but I do not know if I understand what should I do. void CMyAddin::StartProcOut() { IStream* M_stream; LPVOID* izh = NULL; CComPtr oSel; CComQIPtr spApp(m_pParentApp); ATLASSERT(spApp); _bstr_t Some_Text(OLESTR("HELLO?")); hr = CoInitialize(NULL); //return S_OK hr = CoMarshalInterThreadInterfaceInStream(IID_IDTExtensibility2,this,&M_stream); //return S_OK while (end_thread_out == false){ if (WaitForSingleObject(h_end_th_out,INFINITE) != WAIT_FAILED){ HRESULT hr = spApp->get_Selection(&oSel); oSel->TypeText(Some_Text); } } hr = CoGetInterfaceAndReleaseStream(M_stream,IID_IDTExtensibility2,izh); CoUninitialize(); } The CLSID_MyAddin is uniq identifier static const GUID IID_IDTExtensibility2 = {0xB65AD801L,0xABAF,0x11D0,{0xBB,0x8B,0x00,0xA0,0xC9,0x0F,0x27,0x44}}; class CMyAddin : public IDTExtensibility2 Is this correct? I still get: Unhandled exception in WINWORD.EXE 0xC0000005: Access Violation CMyAddin is created by class CMyAddinCF : public IClassFactory Tomaz Rotovnik

:laugh:It is working. Thank you. Tomaz