404 Error on Subcategories post Upgrade to 3.4.1

Hi,

I’m getting 404 error on clicking on subcategories from the main menu post updating wordpress to 3.4.1.

My blog address is https://www.indiapricepoint.com

I’ve already resaved my permalinks but still issue is unresolved. The strange part is that clicking on parent categories is working fine.

For eg when I click on https://www.indiapricepoint.com/electronics it works fine but when I click on
https://www.indiapricepoint.com/electronics/mobile-phones then it gives 404 error

My .htaccess file is also ok and its file permission is 640.
I’m using W2 total cache and WordPress SEO plugin.

Would appreciate help from everyone.

Thanks in advance