How to omit I and O from letters used for references to symbols
Elecdes gives you an option to specify a set of letters you want to use for references to symbols. you can omit the letters "I' and 'O' by removing it from the cross-reference letters set.
From your <EDS> installation open the EL32.INI file.
Scroll down to the [USER – XREF] section.
Locate the "xref_letters" setting and change it to the desired set of letters you want to use for reference to symbols e.g. ABCDEFGHJKLMNPQRSTUVWXYZ ( please notice that this set of letters does not contain letters I and O ).
Save and close the EL32.INI file.