Script from: https://ttboj.wordpress.com/2014/09/30/fixing-dropbox-conflicted-copy-problems

fix-dropbox.sh

$ cat fix-dropbox.sh 
#!/bin/bash

# XXX: use at your own risk - do not run without understanding this first!
exit 1

# safety directory
BACKUP='/tmp/fix-dropbox/'

# TODO: detect or pick manually...
NAME=`hostname`
#NAME='myhostname'
DATE='2014-09-29'

mkdir -p "$BACKUP"
find . -path "*(*'s conflicted copy [0-9][0-9][0-9][0-9]-[0-9][0-9]-[0-9][0-9]*" -print0 | while read -d $'\0' -r file; do
	printf 'Found: %s\n' "$file"

	# TODO: detect or pick manually...
	#NAME='XXX'
	#DATE='2014-09-29'

	STRING=" (${NAME}'s conflicted copy ${DATE})"
	#echo $STRING
	RESULT=`echo "$file" | sed "s/$STRING//"`
	#echo $RESULT

	SAVE="$BACKUP"`dirname "$RESULT"`
	#echo $SAVE
	mkdir -p "$SAVE"
	cp "$RESULT" "$SAVE"
	mv "$file" "$RESULT"

done