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Sorry Kerry, did not know you posted the same thing
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In the ObjectArx 20XX sdk you downloaded there is a folder called docs inside that folder is arxdoc.chm
Which contains the arxmgd.chm and all other .chm's in that folder.
So with that one .chm(arxdoc.chm):
You could type
SendStringToExecute in the textbox on the index tab and get this.
(Notice the sendStringToExecute that starts with the lower case s, that is the ARX command which usually has more info)
Or you could type
SendStringToExecute on the search tab and find info like this