Problems in Admin Panal (no controls)

Hi,

I have been using the NopCommerce 2.65 for some time now, because everytime I try to upgrade to 2.8 or the new 3.0 I lose the Control Panal links and I get error all around.
When I'm logged in and go to the Admin panel, I can only click on the Dashboard.
I can see all the other links like Catalog, Sales etc. But I can't click on any of them.
Also if I click on refresh in the DashBoard, Order Totals etc. I get an error:
The action 'OrderAverageReport' is accessible only by a child request.

What am I missing? Is it some kind of update or javascript somewhere?

Hope somebody can help me with this.

I almost forgot, I have tried to set up a test site, so I could try and install the shop as a new one, but it's the same problem.

You did not properly configured IIS settings

https://www.nopcommerce.com/boards/t/22048/admin-menu-do-not-work.aspx

Thanks a lot, that helped :-)

You are the best