I don't find MT4.EXE File.
There is no "MT4.EXE" file. The MetaTrader executable is "terminal.exe" and you will have to look at the properties of your desktop (or menu) shortcut to see in which directory it is in (see image below).
However, what does that have to do with Excel? Are you trying to use DDE? If so, use the example "DDE-Sample.xls" to get started.
Unfortunately, I don't use DDE and so maybe someone else here can help you out.
Also, I don't know if the "sample" works correctly with newer versions of Excel as it has not been updated by MetaQuotes for a very long time. It still uses the old format.
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