Session protection was added to 2009R1.2C to prevent CSRF attacks. This code to do this caused some users to see this error. The problem was due to the user's browser caching older versions of the XI javascript code. In order to clear the cache and prevent this from happening, you need to clear your browser's cache. This is typically done (in Firefox) by holding down the shift key and clicking reload.
Another possible cause is that the server's time is out of sync with that of the browser. A detailed document that explains all the settings performed can be found here:
Documentation - Changing The System Time
For any support related questions please visit the Nagios Support Forums at:
http://support.nagios.com/forum/
Article ID: 33
Created On: Tue, Jan 27, 2015 at 3:30 PM
Last Updated On: Mon, Feb 22, 2016 at 7:06 PM
Authored by: slansing
Online URL: https://support.nagios.com/kb/article/nagios-xi-nsp-sorry-dave-i-can-t-let-you-do-that-33.html