you can try this way. suppose instruction is jnz loc_1234 ..
then double click on "jnz" , then go to view hex editor .. there you will see bytes for jnz automatically selected .. then right click there on sleected bytes .. select "edit" .. then u done :) . hope this will works for u
Well no need to use Hex Editors though. You can make use of Immunity/Olly to change the instructions on the fly. That would be more convenient than changing the opcodes through Hex Editors.
Hope it helps!
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