How to kill Excel process?

Hi,
I'm doing an action in first debug like this:
1, Create excel instance.
2, During debugging, turn it off suddenly.
In some case, this processes still run in background,
so when i use getobject code get the instance but now they are no longer valid.

I used the following code in second debug but it doesn't work?

//check [getobject] if catch error then terminate process and create new one:
::PostMessage(hWnd, WM_CLOSE, 0, 0);

How do I kill this process?



Thanks you!

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