I gave this a try and nothing worked.
I spent all weekend trying to find a fix.
I looked at my laptop which had no problems and looked at my wife's which has the problems..
What I did was to go to this folder on my laptop called "Recent"
Had nothing to lose
In there are to folders called:
I copied them to my memory stick and then went to my wife's PC and replaced everything in her C:\Users\wife\AppData\Roaming\Microsoft\Windows\Recent\
with my 2 folders.
(removed everything before I copied the 2 folders from my Laptop to her's I made a backup on her desktop of the items and folders just to play it safe.)
Restarted the her PC and now all the jump list arrows are back and working.
Hope this works for others