OK, are your chat logs in text or HTML? More importantly are your chat logs encrypted?
I'm not entirely sure, so don't count me on this, but I believe you cannot edit encrypted chat logs. You can edit none encrypted logs. Text logs should be easy, but if you are using HTML you will need to know exactly what to edit .
I'm sorry I cannot help any further, but I know little about how chat logs work in Messenger Plus! Live.
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