I am trying to modify an exe (of mine) with a hex editor.  It was originally written in Python using wx and turned into an exe via py2exe.  I lost the source code (ugh) and need to change one of the items in a dropdown menu.  It's a simple one character change, from a "6" to a "9". (Makes me think of Jimi Hendrix)
I have used several hex editors, and I can find the string and make the change and save the file.  However, when I open the modified exe, the drop down entry has not changed.  I can verify that the exe is different by opening it in the hex editor again and checking, and the string is set to the new value I need.  It just doesn't display that way when running the app.  
I obviously don't play with hex editors (or hex, for that matter) much.  What am I missing?  TIA.
You may find this next to impossible to do this way, since there could be thousands of characters like this in the exe.  You'd probably be better off first searching for a less common item in your dropdown to give you a better chance of finding the "area" where it may be occurring.  Then do a more localized search nearby for the "6".  Even then, there's no guarantee these dropdown items will be located near each other in the executable (but I think it likely).
Hexedit of ASCII in exe not changing in app