Scenario:
So you just upgraded your Magento store to the latest version 1.3.1. Everything seems fine except the fact that now all of a sudden all of your products seem to be in stock! You know you don’t have those products in stock and before you upgraded all of the quantities were correct. All you need to do is to ‘refresh’ your ‘inventory stock status.’ This is super easy and works like peanut butter and jelly.
The Solution:
You need to refresh your cache.
1. Log in to your Magento Admin. Go to System.
2. Go to Cache Management.
3. Find ‘Inventory Stock Status’ under the ‘Catalog’ title.
4. Click ‘Refresh.’
Problem solved.
Keep it real!

