Where have my captions gone?

I have an annoying problem

I have lost the captions to the thumbnails in My Computer on my XP Home SP3

see http://homepage.ntlworld.com/cdwainwright/MyComputer.jpg

This only happens in thumbnail mode and on one user profile - all other display modes (icons, tiles etc) and users are fine.

Does anyone have any ideas how to get them back?

Thanks