Getting to this point ultimately lead to the resolution. Below is the process we used to solve the reindexing issue for Product Flat Data:
1) Export all catalog_product_flat _* tables with data and structure with “Disable foreign key checks” enabled.
2) Drop all catalog_product_flat _* tables.
3) Once check in Frontend , that products are categories are visible
4) Login to Magento backend
5) Go to: System -> Index Management
6) Click “Reindex Data” next to “Product Flat Data” index
Below is the process we used to solve the reindexing issue for Category Products (Indexed category/products association):
1) Log into phpMyAdmin
2) Go to `catalog_category_product_index`
3) Click “Export”.
4) Export only structure with “Disable foreign key checks” enabled.
5) Drop the table `catalog_category_product_index`
6) With the SQL that was exported, remove the constraints at the bottom of the export. Be sure to keep the “SET FOREIGN_KEY_CHECKS” statements.
7) Click “SQL”, paste in modified SQL and click “Go”
8) Login to Magento backend
9) Go to: System -> Index Management
10) Click “Reindex Data” next to “Category Products” index
This worked for me ..Hope it will help you too.
If it helps dont forget to comment me ..