This will not allow the Shell to interact with your instance through DDE,
i.e. double-clicking and Excel file in Explorer:
Application.IgnoreRemoteRequests = True

It is still accessible via COM, but the user cannot inadvertently use that.

NickHK

"How to reject user operation"
m wrote in message
...
Thanks a lot Vergel Adriano
I didn't use visible currectly, thank you for reminding me.
I didn't well explain my problem, my real problem is I want to reject
user access to the Excel process I created.
for example:
I created a Excel Process(Process Id is 1868---allocated by OS ), and
when user open a excel file, I don't want user to share the same process.
I
want to create a Excel process only for my program. Is there any method.


"Vergel Adriano" wrote:

The Excel instance opened through automation shouldn't be visible. Make
sure
you don't have any line like this in your code:

m_exlApp.Visible = True

If you need the Excel instance to be visible, you can set the
Interactive
property to false.

m_exlApp.Interactive=False