This may occur because the CNA site has a session time-out restriction; if a user has accessed the site but has not taken any action for a certain period of time, he or she will be required to log in again.
To resolve this issue, instruct the user to do the following:
Close the CNA window and return to the ISG Central homepage.
Click on the CNA tab on the left side of the homepage.
If the user has been disabled, please contact your Canon regional representative for assistance.