Fortunately I was able to solve the issue myself. I'll post my findings here for anyone else having the same issue.
The problem was indeed with JoomSEF and when taking a look at the ‘SEF’ URL’s it created, I noticed there were 4-5 different URL’s pointing at the same ‘SEF’ URL for many products. This was more than likely the clients fault for not using JoomSEF properly.
For example, this link here…
www.walnutmelbourne.com.au/virtuemart/lo...-leather-ballet-bone
… was pointing to:
- index.php?option=com_virtuemart&category_id=157&flypage=flypage.tpl&manufacturer_id=1&page=shop.product_details&product_id=5403
- index.php?option=com_virtuemart&category_id=42&flypage=flypage.tpl&manufacturer_id=1&page=shop.product_details&product_id=5403&Itemid=100046
- index.php?option=com_virtuemart&category_id=111&flypage=flypage.tpl&manufacturer_id=1&page=shop.product_details&product_id=5403&Itemid=100046
So I took the liberty of going through every single published children’s and ladies product in the store, finding the broken ones and fixing them. I was then able to go ahead and add the ‘other colours’ (additional products in same category) code back in and it is now working perfectly!
Also, the stockists page issue was resolved in a similar way. It only had one SEF URL so I just deleted it and rebuilt it. It’s now working perfectly too.