EscapeE provides two mechanisms for avoiding output files overwriting existing files.

If the Do not overwrite files checkbox is ticked when Exporting files then if a subsequent file is created which would have the same name as a file in the list, EscapeE appends "#1", "#2" etc. to the new file's name automatically. This ensures that each file name is unique and that no existing files are overwritten.
If the box is unchecked then EscapeE maintains a list of output files that have been created from the most recently opened file and appends "1", "2" etc to the name if it would be the same as one created earlier in the run (but not considering any pre-existing files). The file list is cleared when a input new file is opened.

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