Unable to open CF 11 cfusion adminstrator page

Hi,

I have a CF 11 for my testing environment.

I have set an instance in that application. The issue is I can open my instance administrator page but can't open the cfusion one.

It just gave me a blank screen and when I look the server log it said the session manager is failed.

Has anyone has a similar issue and know how to solve it?

Please let me know if you need more information. Thank you.

Kind Regards,

Raquel Septiane