I've just run a quick test on my machine here and used the following script:
with the following in a command prompt window:
Dim ObjFolder, ObjFolderItem, colVerbs, objverb, objshell
Set objShell = CreateObject("Shell.Application")
Set objFolder = objShell.Namespace("C:\Program Files\WinRAR")
Set objFolderItem = objFolder.ParseName("WinRAR.exe")
Set colVerbs = objFolderItem.Verbs
For Each objVerb in colVerbs
If Replace(objVerb.name, "&", "") = "Pin to Start Menu" Then objVerb.DoIt
This pinned WinRAR into the start menu for me successfully. I would therefore recommend for a user who this did not work for on your systems look at the script line by line and test the path, exe name. Also when you right click on the Exe you are trying to pin that "Pin to Start Menu" does exist in the context menu.
Microsoft (R) Windows Script Host Version 5.8
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