This is a very common exception and is thrown when you try to use a view that has already expired (expiration depends on many factors).
We need more information of your situation. When exactly are you getting this exception etc
I am using richfaces, JSF 2. I want execute some methods repeatedly(5 seconds) to update trading portal(web page) . but when i logging to trading portal that error coming. Not Session Timeout.
Thanks in advance
View timeout and session timeout are not related. The View is the digested JSF page definition. Depending on web.xml, it can either be stored on the server or passed back and forth to the client. For a number of reasons, the preferred approach is to cache views on the server, but to conserve resources, views are periodically purged from the server's view cache. When that happens and a request is made to redisplay the view, you get a ViewExpiredException.
Adjusting session parameters will do no good, since, as I said, the cached views aren't coming from the session.
There are some web.xml settings you can make to control JSF view timeout. I recommend you read up on them.
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