Crash in GetMAPIOBJECT + Outlook 2007

[pete_42]

Hi,

I'm using the following code to get the IMAPIProp-Pointer to the
current Outlook mail window. Worked nicely so far. But when I'm testing
it with Outlook 2007 beta, the GetMAPIOBJECT call causes an exception.

If I perform the same steps as the program below does with OutlookSpy
and Outlook 2007 everything works nicely - so what am I doing wrong,
here? I'd be grateful for any ideas...

THANKS!

pete

Outlook::_InspectorPtr spInspector = m_OLAppPtr->ActiveWindow();
if (spInspector)
{
IDispatch *pd = spInspector->GetCurrentItem();
if (pd)
{
Outlook::_MailItem *pMailItem = NULL;
const GUID local_IID_IMailItem = {0x00063034,0,0,
{0xC0,0,0,0,0,0,0,0x46}};
pd->QueryInterface (local_IID_IMailItem, (LPVOID *)&pMailItem);

if (pMailItem)
{
IUnknown *iu = pMailItem->GetMAPIOBJECT(); //Crashes in
Outlook 2007 Beta
.....

 

[Dmitry Streblechenko]

Where is your code running? Is it in the outook.exe process space (your code
is a COM add-in) or in a separate exe?

Dmitry Streblechenko (MVP)
http://www.dimastr.com/
OutlookSpy - Outlook, CDO
and MAPI Developer Tool

 

[pete_42]

Where is your code running? Is it in the outook.exe process space (your code
is a COM add-in) or in a separate exe?

It's an add-in.

 

[Dmitry Streblechenko]

Hmmm... What kind of exception is it? A COM error or something like an
access violation?

Dmitry Streblechenko (MVP)
http://www.dimastr.com/
OutlookSpy - Outlook, CDO
and MAPI Developer Tool

 

[pete_42]

Hmmm... What kind of exception is it? A COM error or something like an
access violation?

Good question. I tried 3 catch'es:

catch(_com_error &)
catch (CException *)
catch (...)

The third one caught the exception. So it's probably an access
violation.

Can the pointer be wrong?
Am I doing a bad cast somehow??

 

[Dmitry Streblechenko]

What happens when you run your code under the debugger? Did you set "break
on exception" for all exceptions in Debug | Exceptions dialog?

Dmitry Streblechenko (MVP)
http://www.dimastr.com/
OutlookSpy - Outlook, CDO
and MAPI Developer Tool

 

[pete_42]

Took some time, but I got some
1. pMailItem->Save();
Works most of the time. (Currently I don't worry about RARE crashes)
2. pMailItem->get_MAPIOBJECT(...);
Works most of the time, about always yields a NULL pointer.
3. pMailItem->get_Class(...)
Works most of the time and yields 43.

=> So the pMailItem Pointer should be correct.

If I compile my DLL in debug mode (Previously I used release mode for
an easier deployment on the other PC), I get an error messagesaying
the ESP wasn't properly restored, probably because of differing calling
coventions. So I guess that my include files (Generated from Outlook
2000) are bad.

Quoting from msoutl9.tlh:

__declspec(property(get=GetMAPIOBJECT))
IUnknownPtr MAPIOBJECT; and
virtual HRESULT __stdcall get_MAPIOBJECT (
IUnknown * * MAPIOBJECT ) = 0;

Quoting from msoutl9.tli:

#pragma implementation_key(564)
inline IUnknownPtr Outlook::_MailItem::GetMAPIOBJECT ( ) {
IUnknown * _result;
HRESULT _hr = get_MAPIOBJECT(&_result);
if (FAILED(_hr)) _com_issue_errorex(_hr, this, __uuidof(this));
return IUnknownPtr(_result, false);
}

But this yields new questions:
- Does GetMAPIOBJECT really call get_MAPIOBJECT? If so, why don't I get
a crash for the latter and why does Microsoft recommend no to use
get_MAPIOBJECT?
- Is the include bad? And how? Is _stdcall or HRESULT or IUnknown
defined wrong by some include?
- Is there another way to call the function? Some generic
Invoke/Message/Whatever?
- Which call do you perform in OutlookSpy when I doubleclick the
MAPIOBJECT item in the CurrentItem() View?

Thanks.

 

[Dmitry Streblechenko]

Don't know about the headers - I don't use VC++. Did you try to create new
headers using the Outlook 2007 type library?
OutlookSpy always uses late binding when retrieving that property - call
IDispatch::GetIDsOfNames("MAPIOBJECT", ...) then IDispatch::Invoke().

Dmitry Streblechenko (MVP)
http://www.dimastr.com/
OutlookSpy - Outlook, CDO
and MAPI Developer Tool

 

[pete_42]

YESYESYES!!!!!

Now it works. If I Invoke() the call manually it works. But now I found
a different problem.

Once I Save an unsaved mail, the "pMailItem" seems to become bad. I
can't pMailItem->Release it. Or Invoke Save again. Both causes a crash.

Does the Save invalidate the pMailItem? Don't I have to release it? Or
do I have to wait for the Save to finish? Somehow...

 

[Dmitry Streblechenko]

I have never seen or heard about such a problem with MailItem.Save.
I strongly suspect that something happens in your code

Dmitry Streblechenko (MVP)
http://www.dimastr.com/
OutlookSpy - Outlook, CDO
and MAPI Developer Tool

 

[pete_42]

I have never seen or heard about such a problem with MailItem.Save.
I strongly suspect that something happens in your code

I know, it sounds very suspicious. (For me, too ;-) But now, when I
Save an Item that has not been saved previously I call ActiveWindow()
and GetCurrentItem() again (basically re-getting the pointer) and it
works. I've removed the QueryInterface-Call to the GetCurrentItem()
result, so there shouldn't be memory leaks.

Don't ask me why, but it works.

Dmitry, thanks a lot for all your help and comments!

 

[Dmitry Streblechenko]

So you call Save on an item that is being displayed?
Can you check the evalue of MailItem.Parent.Name before and after saving?

Dmitry Streblechenko (MVP)
http://www.dimastr.com/
OutlookSpy - Outlook, CDO
and MAPI Developer Tool

 

[pete_42]

So you call Save on an item that is being displayed?

Yes. Because I want it to have an PR_ENTRYID member.

Can you check the evalue of MailItem.Parent.Name before and after saving?

Didn't try that. But if you're really interested, I can do that.

My impression is that the Save() Call to an unsaved message makes the
MailItem-Pointer invalid (under Outlook 2007). Perhaps the item is
somehow moved/converted/copied, because I think the Problem occurs only
for a Save() call on an unsaved item. Because even Release() failed (on
the copy that I got with QueryInterface) I doubt that any other call
would succeed.

 

[pete_42]

Dmitry, did you notice that the tooltip for the OutlookSpy button
"Application" is multi-line for the main window, but not when the
button appears in a mail window?

Is that an Outlook 2007 bug?

Wouldn't be the only one. I've noticed that you don't get reasonable
values when you query a toolbar button's size or position...

 

[Dmitry Streblechenko]

It is an OutlookSpy bug

Dmitry Streblechenko (MVP)
http://www.dimastr.com/
OutlookSpy - Outlook, CDO
and MAPI Developer Tool

 

[pete_42]

It is an OutlookSpy bug

How do you fix that? (I'm having the same problem... ;-)

 

[Dmitry Streblechenko]

You need to include the carriage return (0xD, 0xA) in the string that you
assign to the CommandBarButton.ToolTipText property.

Dmitry Streblechenko (MVP)
http://www.dimastr.com/
OutlookSpy - Outlook, CDO
and MAPI Developer Tool