"Find Full File Names Greater Than 255" tests the length of file names including their path.
I make backups of my data with copy and paste and sometimes the following Windows error occurs:
Error Copying File or Folder
Cannot copy "filename":
The file name you specified is not valid or too long.
Specify a different file name.
This stops the file copy at an undetermined point and requires starting over.
"Find Full File Names Greater Than 255" will find all file names with a length greater then 255 or as specified.
User can then double click file name and a Windows file window opens for editing the file name.
See Find Full File Names Greater Than 255