price with and without tax the same in backend.

The problem that occurred is when i input the price off the product either in the tab with or without tax the price stays the same.
In the front-end rather i get the price including the tax. That's very strange because i have to calculate the price without tax in the back-end to get the price with tax in the front-end.
I did make some tax rules and also categories but nothing will give me a satisfied result. What could be the problem ???
I also attached some scrennpictures.

Hi,

The taxes on the backend is calculated based on the main tax zone that you set in the configuration or based on your user address. So make sure that your user address is in the Netherlands and that your main tax zone is also Netherlands and you should definitely get the taxes on the prices of the backend.
Note that you will have to logout/login to see the effect of your change.