Having a problem with quantity on hand (available) not showing on product screen. Also, entering a line on sales order always results in a warning of '0' available.
When updating QOH either through the 'Update Qty On Hand' button on the product screen or through an inventory adjustment everything looks fine in inventory.
The 'On Hand' always shows '0' on the product view even after making the adjustment. When clicking 'On Hand' it brings up the inventory location(s) and shows the quantities there just fine.
When trying to add the product on a sales order line the no stock warning appears.
This happens with an existing product item or newly created product always the same result.
This seems to be virtual_available is not calculated correctly. Obviously something is not configured correctly. Everything works fine on a test 'demo' Odoo 9 database.
Do you have more than 1 warehouse? Maybe you adjusted the inventory in Warehouse A and are trying to sell from Warehouse B. If you can reproduce the issue at runbot.odoo.com, report at help@odoo.com, but it definitely sounds like a configuration problem.