Using Bulk Rename Utility you may rename files based on folder names and save hours renaming those pesky hashed file names.
Follow these steps:
On the left pane (the folder tree) select "E:\Vacations".
In Selections (12) check only "Files" and "Subfolders".
Set Numbering (10) as "Mode = Suffix", "Pad = 3", "Sep. = ." and check the "Folder" option.
In File (2) select "Remove".
In Append Folder Name (9) select "Prefix".
Make sure you have your files selected (press CTRL+A or use the "Actions > Select All" menu.)
Now you can preview the results on the right pane, and, if everything's ok, just press "Rename".