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The session expiration time is set to low value on the web server. The logon state session expires because of inactivity while user fills the last post ad page. To extend session for Rapid Classified Application, open config/config.asp configuration page in any text editor and insert line:
Session.Timeout = 25
anywhere on this page. 25 represents the time in minutes before session expired because of inactivity. Do not set this value to an extensive (over 30-40 minutes) period because it will affect server's performance specifically if you have a great number of visitors.
Note: Depending on server configuration, this solution might or might not work. Inquire your hosting support in this case.
Version v3.2 / v3.2c / v3.15 / v3.3 / v4.0
2 hours is the default session for user logon state. That is user has 2 hours to complete filling ads data by default.