Unable to validate report or set view parameters

[Rosanero4Ever]

Hi all,

I'm using Cognos BI 10.2 FP4 and I have a very strange behavior...
When I need to validate a report or I need to set parameters in a view report or I need to perform any other action that triggers the popup window with filters (with OK and Cancel buttons in the bottom of the window) nothing occurs when I click on the OK button!!
I tried using different browsers and browsers version and different PCs
I also restarted Cognos service withous success
I analyzed the cogserver.log but no records are stored when I click on the OK button
Does anybody can advice me anything to understand what I have to explore in order to solve the issue?
Many thanks in advance