How to reduce the size of thumbnails that I want to send as email attachments?

I used to be able to reduce the size by the following method, but it does not work with WINDOWS 8.1.

The old method:-

1. Highlight thumbnails in PICTURES folder.
2. Open thumbnails with Photoshop CS5.
3. Use "magnifying glass" icon with the MINUS sign to
reduce size of the pictures.
4. Save the pictures, NOW REDUCED in size, in PICTURES folder.
5. Right-click on the thumbnails reduced in size and click on SEND TO
MAIL RECIPIENT in the drop-down menu.
6. In the window headed SEND PICTURES VIA E-MAIL, check the wording
"Make All My Pictures Smaller".

The problem:- Step 6 is not available in Windows 8.1

Grateful for any help.

Joe (from Malta EU)