#!/bin/sh

for FILE in $(find . -type f -name '*4%3a*'); do
  NEWNAME=$(echo $FILE|sed s/'4%3a'//)
  mv -v $FILE $NEWNAME
done

#!/bin/sh

# first we need a list to work from.  the
# "for" statement will loop through the results
# of our "find" command, using each result in turn
# as "$FILE".  The find command that I used will
# recursive look in subdirectories as well.  You can
# fix that with a flag, or you could use something
# like `ls |grep '4%3a'`
for FILE in $(find . -type f -name '*4%3a*'); do

  # here we use sed to get rid of the unwanted string
  # and store it as "$NEWNAME"
  NEWNAME=$(echo $FILE|sed s/'4%3a'//)

  # here we do the actual work!
  mv -v $FILE $NEWNAME

done

# ./script.sh -s "4%3a" -e "" -d "*.deb" # display all files to be renamed
# ./script.sh -s "4%3a" -e "" -d "*.deb"  #remove -d to do actual rename