AuthenticationHelper RemoveSessionID Method Kentico 8.1 API Reference
Removes cookie with session ID which enforces ASP.NET to generate new session ID if RenewSessionAuthChange property is set to true.

Namespace: CMS.Membership
Assembly: CMS.Membership (in CMS.Membership.dll) Version: 8.0.0.0 (8.1.5347.20411)
See Also
AuthenticationHelper Class
AuthenticationHelper Members
CMS.Membership Namespace