I suggest to use font Courier New and switch to OEM Character Set. If you can't see that menu item in menu View, see Manual customization of OEM Character Set command for help on how to add this command to the menu or toolbar.
Well, that's bad. View - Set Code Page is only for specifying the code page used for conversion from Unicode to ASCII/ANSI and vice versa (and local specific sorts). It has no influence on the glyphs used for displaying the bytes in an ASCII/ANSI file as characters. Only the selected font and the selected script is responsible for the display of the bytes as characters. So you need a font which supports DOS codepage 866.
Or you try following: After selecting the codepage use File - Conversions - ASCII to Unicode to convert your file to Unicode. This character set contains nearly all characters of all languages. So you should see now the correct characters. When you are finished with editing, convert the file back to ASCII and save it.
Best regards from an UC/UE/UES for Windows user from Austria
