Products are exist but not shown on website

My zen cart version is 1.03.07.
I have been trying to improve mywebsite but it seems that I have made some mistakes while editing some features.
Three sub -categories (out of five) with all the products in them are not showing online, the other 2 categories and products are shown.
The hidden products are still in the admin and I did not delete them.
Has anybody encountered a similar case, and would it be the cause?
My website url is: artiquea.co.uk, and the hidden products are under sub categories: pioneer artists, traditional artists and contemporary artists.

Sam/artiquea

make sure you have not disabled those subcategories .by going to catalog > Categories / Products and look to see if category or its sub category is enabled ( Green Icon ) if is not green then click on the icon to enable them back .