Session
Time Out is
20 minutes by default.
The value is affected in a number of settings including
Application Pool, ASP, ASP.NET Session State, CookieTimeout.
Please follow instruction below to configure Session Time Out on IIS
Open IIS Manager
Application Pool -> Advanced Settings -> Process Model -> Set Idle Time-out in minutes
Sites -> your-website-domain.com -> ASP -> Session Properties -> Time-out then Apply Change
Sites -> your-website-domain.com -> Configuration Editor -> system.web/sessionState -> Set Timeout value then Apply Change
Sites -> your-website-domain.com -> Configuration Editor -> system.web/roleManager => Set cookieTimeout then Apply Change
Ref:
IIS configure ASP.NET Session Time Out[
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