How to Add File Extensions with Bulk Rename Utility
If you have a set of files which are missing file extensions, and you want to add the same extension to each, you can use this quick fix in Bulk Rename Utility:
In the Regex Match / Replace section on the upper left, enter the regular expression: (.+) in the Match box, and then \1.pdf in the Replace box, assuming you're dealing with files in the PDF format.
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