You can rename files in the phone subfolders.
Renaming files in the phone subfolders requires extra free memory. The amount of free memory required is the same as the size of the file to be renamed. If you get a message stating that there is not enough free memory on the phone to perform this operation, delete some files from the phone and try again. If you do not want to delete files from the phone, rename the files directly in your phone.
Renaming files in the phone subfolders may take some time.