Taxes backend don't appear in final price

[damsoi01]

Hello everyone,

 

I updated today my shop to 1.6.1.5 and I have an issue: when creating a product and indicating a price before taxes the calculation does not apply and the price displayed in the "tax included" field is the same as the one without taxes. Same when I am in the catalog list the column of final price is identical to the original price.

HOWEVER my shop is well configured since in frontend the prices are displayed as usual with taxes included. 

 

What coud be the reason of this new error showing after the upgrade, and how to fix it?

 

Thanks!