All,

I have a mobile control ASP.NET application which uses VB.NET objects.
Application works fine if I just test it using one browser session.
If I open two browsers then after a call to my vb.net object, one of
my browsers give me this error

The page requires session state that is no longer available. Either
the session has expired, the client did not send a valid session
cookie, or the session state history size is too small. Try increasing
the history size or session expiry limit.

My session timeout limit is 20 minutes and
sessionStateHistorySize="10" That vb object only takes few seconds, so
I know it is not session timeout.  I am not sure what
sessionStateHistorySize is.  I tried to increase it to 100 but still I
get the same error.

Any idea?

Thanks