Some third party DLL loaded by GetOpenFileName is corrupting my memory. I want to know which so I can uninstall the program.
Due to a well known problem with adobe reader, I do call ::OleInitialize(NULL) right in the beginning of main(). But even with that hack, once I hover over a filename inside the GetOpenFileName dialog and the tooltip appears, my app's memory is corrupted and it actually crashes when it receives a WM_PAINT and tries to access that memory.
I want to break the debugging as soon as any code writes in that memory. Is it possible?
[source]

OPENFILENAME _ofn;
vector<char> _Filename(1024); // buffer for file name
//vector<char> _Filename(MAX_PATH); // buffer for file name
::ZeroMemory(&_ofn, sizeof(_ofn));
_ofn.lStructSize = sizeof(_ofn);
_ofn.hwndOwner = *_Owner->Qdwindowp;
_ofn.lpstrFile = &_Filename[0];
// Set lpstrFile[0] to '\0' so that GetOpenFileName does not
// use the contents of _Filename to initialize itself.
_ofn.lpstrFile[0] = '\0';
_ofn.nMaxFile = _Filename.size();
_ofn.lpstrFilter = _Filter;
_ofn.nFilterIndex = 1;
_ofn.Flags = OFN_EXPLORER | OFN_PATHMUSTEXIST | OFN_FILEMUSTEXIST |
OFN_HIDEREADONLY | ( _Allowmultiselect ? OFN_ALLOWMULTISELECT : 0 );
::GetOpenFileName(&_ofn);

[/source]

Thanks for the help. This problem is too hard. I think I am gonna quit, and hope that most people won't have this problem when opening a file.
I have already uninstalled adobe reader but the problem persists.

GetOpenFileName loads all these DLLs as soon as the dialog shows:
[source]
'pasion2.exe': Loaded 'C:\WINDOWS\system32\apphelp.dll'
'pasion2.exe': Loaded 'C:\WINDOWS\system32\clbcatq.dll'
'pasion2.exe': Loaded 'C:\WINDOWS\system32\comres.dll'
'pasion2.exe': Loaded 'C:\WINDOWS\system32\oleaut32.dll'
'pasion2.exe': Loaded 'C:\WINDOWS\system32\version.dll'
'pasion2.exe': Loaded 'C:\Program Files\Common Files\TortoiseOverlays\TortoiseOverlays.dll'
'pasion2.exe': Loaded 'C:\Program Files\TortoiseSVN\bin\TortoiseStub.dll', Binary was not built with debug information.
'pasion2.exe': Loaded 'C:\Program Files\TortoiseSVN\bin\TortoiseSVN.dll'
'pasion2.exe': Loaded 'C:\WINDOWS\system32\wininet.dll'
'pasion2.exe': Loaded 'C:\WINDOWS\system32\normaliz.dll'
'pasion2.exe': Loaded 'C:\WINDOWS\system32\urlmon.dll'
'pasion2.exe': Loaded 'C:\WINDOWS\system32\iertutil.dll'
'pasion2.exe': Loaded 'C:\Program Files\TortoiseSVN\bin\libapr_tsvn.dll'
'pasion2.exe': Loaded 'C:\Program Files\TortoiseSVN\bin\libaprutil_tsvn.dll'
'pasion2.exe': Loaded 'C:\WINDOWS\system32\wldap32.dll'
'pasion2.exe': Loaded 'C:\Program Files\TortoiseSVN\bin\intl3_tsvn.dll'
'pasion2.exe': Loaded 'C:\WINDOWS\WinSxS\x86_Microsoft.VC90.CRT_1fc8b3b9a1e18e3b_9.0.30729.1_x-ww_6f74963e\msvcp90.dll'
'pasion2.exe': Loaded 'C:\WINDOWS\system32\shfolder.dll'
'pasion2.exe': Loaded 'C:\WINDOWS\system32\cscui.dll'
'pasion2.exe': Loaded 'C:\WINDOWS\system32\cscdll.dll'
'pasion2.exe': Loaded 'C:\Program Files\TortoiseCVS\TortoiseShell.dll', Binary was not built with debug information.
'pasion2.exe': Loaded 'C:\WINDOWS\WinSxS\x86_Microsoft.VC80.CRT_1fc8b3b9a1e18e3b_8.0.50727.3053_x-ww_b80fa8ca\msvcp80.dll'
'pasion2.exe': Loaded 'C:\WINDOWS\WinSxS\x86_Microsoft.VC80.CRT_1fc8b3b9a1e18e3b_8.0.50727.3053_x-ww_b80fa8ca\msvcr80.dll'
'pasion2.exe': Loaded 'C:\WINDOWS\system32\browseui.dll'
'pasion2.exe': Loaded 'C:\WINDOWS\system32\setupapi.dll'
'pasion2.exe': Loaded 'C:\WINDOWS\system32\ntshrui.dll'
'pasion2.exe': Loaded 'C:\WINDOWS\system32\atl.dll'
'pasion2.exe': Loaded 'C:\WINDOWS\system32\netapi32.dll'
'pasion2.exe': Loaded 'C:\WINDOWS\system32\userenv.dll'
'pasion2.exe': Loaded 'C:\WINDOWS\system32\shdocvw.dll'
'pasion2.exe': Loaded 'C:\WINDOWS\system32\crypt32.dll'
'pasion2.exe': Loaded 'C:\WINDOWS\system32\msasn1.dll'
'pasion2.exe': Loaded 'C:\WINDOWS\system32\cryptui.dll'
'pasion2.exe': Loaded 'C:\WINDOWS\system32\wintrust.dll'
'pasion2.exe': Loaded 'C:\WINDOWS\system32\imagehlp.dll'
[/source]

Then as I hover the tooltip it also loads the following:
[source]
'pasion2.exe': Loaded 'C:\WINDOWS\system32\xpsp2res.dll', Binary was not built with debug information.
'pasion2.exe': Loaded 'C:\WINDOWS\system32\shimgvw.dll'
'pasion2.exe': Unloaded 'C:\WINDOWS\system32\shimgvw.dll'
[/source]

Most of these DLLs are system and there is nothing I can do about it. I will uninstall SVN and give it another try.

Unfortunately the data breakpoint is not working either. I set a data breakpoint to the memory pointed by Texturebrushp:
[source]
BOOL Mainwindowprivate::virtual_wm_create ( HWND hwnd, LPCREATESTRUCT pcs )
{
Containerprivate::virtual_wm_create ( hwnd, pcs ) ;

Wallpaperbitmapp = LoadImage( "Wallpaper", "jpg" ) ;
Texturebrushp = new TextureBrush( Wallpaperbitmapp );

python_wrap_staticcallback( reinterpret_cast<void(*)()>(
&connect_initialize), "connect_initialize" );
PyModule_AddObject( PyImport_AddModule("application"),
"country_listcallback", python_create_void(
&Countrylistcallbacko ));
python_import( "Mainwindow" );
python_call_method( "Mainwindow.Mainwindow", "(N)",
python_create_container( this ));

return TRUE;
}

[/source]

Texturebrushp is never deleted in the life of the program.

After the dialog opens I do "break all" and check the memory, everything is still ok.
Then after a tooltip is displayed, I "break all" again, and get the attached image. All question marks.
Texturebrushp points to 0x010df650. This memory belongs to my process and I never dealocated it. Strange.

There's one thing I picked up on: Casting function pointers is a bad idea. You should fix the declaration of the function instead of using a cast.

Solved it!!!!
It was bloody SVN shell extension.
Still one question remains: if the SVN shell extension I installed corrupts memory, how come it does not crash Windows Explorer itself?