PostMessage crashes crash...

[Demonpiggies]

I have created a new section of the already cramped status bar to display member information of a specific class. I am trying to do this be means of a PostMessage() but my application crashes when I run it in Release (but not in Debug).

Here are the custom messages (from defines.h):

#define WM_CUSTOMMESSAGE_FIELD_SELECTED WM_USER+12
#define WM_CUSTOMMESSAGE_FIELD_DESELECTED WM_USER+13

Here is me handling the messages (from MainFrm.cpp):

ON_MESSAGE(WM_CUSTOMMESSAGE_FIELD_SELECTED, OnUpdateFieldInformationSelectedStatus)

ON_MESSAGE(WM_CUSTOMMESSAGE_FIELD_DESELECTED, OnUpdateFieldInformationDeselectedStatus)

And here is the PostMessage (from CField.cpp):
BOOL CField::SelectField( CWnd* pWnd, CPoint* cptMouse )
{
.
.
.
if(pWnd)
{
pWnd->PostMessage(WM_CUSTOMMESSAGE_FIELD_SELECTED, NULL, NULL);
}

return TRUE;
}

When the user selects a field a message is posted and the status bar is updated. But this does not happen correctly. As stated before, the application crashes. I have read MANY articles on this and have failed to come up with anything useful. To clarify the application crashes AFTER the status bar has been updated and I do not know why. The crash happens right after the message is picked up and OnUpdateFieldInformationSelectedStatus is finished. If I take out the PostMessage the application is fine. I have tried SendMessage() but this crashes the application sooner than PostMessage(). If I can the method directly I get initialized information (meaning everything I pull from the CField object is initialized to 0) yet if I use PostMessage I get the correct data. I am not looking to rewrite the CField of the application but if someone could help me fix this PostMessage issue I would be grateful.