I have a requirement that wrapped MFC¡¯s CHtmlView into a COM object that
could open all kinds of office document for previewing. But when I use
Navigate() method open a xls file in our program and at the same time I
opened another xls file in a standalone excel application, I could not
switch between our program and excel application. The focus seems always on
our program.

Does anybody know why?

BTW, more info are that,
1. If drag and drop a xls file directly into IE, it is ok. There is no
problem to switch between IE and the standalone excel app.

2. This weird behavior is not always existing. I have test in 5 computers
and got the results as:

Enviroments Has weird behavior?

WinXP + SP2 + IE7 + Office 2003: Yes
WinXP + SP2 + IE7 + Office 2007: Yes
WinXP + SP2 + IE6 + Office 2003: No (I have test 3 computer with the same
environments only 1 is ok.)