Select the web application under the web site to show the Features View of the web application.

01-SG-FAQ

Double-click the Authentication feature to open the Authentication view.

02-SG-FAQ

 

Select Forms Authentication in the view and then click the “Edit…” link to bring up the Forms Authentication Settings dialog window.

03-SG-FAQ

Enter your value in the “Authentication cookie time-out (in minutes):” box.
Return to the Features View of the web application.

05-SG-FAQ

 

Double-click the Session State feature to open the Session State view.

06-SG-FAQ

Enter your value in the “Cookie Settings” -> “Time-out (in minutes):” box. Then click the “Apply” link in the upper right.