Ed:
re:https://help.dropbox.com/syncing-uploads/white-space-conflict
=== it really does not say much at all ===
What's a white space conflict?
If two files with almost the exact same name exist in the same folder of your Dropbox, but the only difference is an extra space in the name of the file, a white space conflict will occur. Dropbox would rather be extra careful about saving your file if the file name is not identical in any way, so it will create a copy of the file rather than replace the existing file. The most recently changed copy will be appended with "white space conflict".
To reconcile the conflict, either rename the conflicted file to something unique, or make sure you avoid renaming the file with an extra space or character the next time you save the file.
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not very helpful. We should be able to use any file name we choose. period. your software "thinks" there is an error, but there is None. Just save the file with the Same Name...
file names are often generated by the User Software. It Works. Dropbox is the problem.