"viewstate is invalid for this page and might be corrupted" - why does worker process recycling cause this?

[Trevor Andrew]

Hi There,

I have posted something previously regarding this issue, but I think I have
some more concise questions to ask, and would like to get further feedback
on this issue.

Firstly the background. I have a small ASP.NET application under
development. I'm using VS 2002 with Framework 1.1. One of the pages is a
"resources" page that contains a list-box of various RSS feeds I am
interested in surveying. As you select the different RSS feed topic, the
articles are shown on the page below. If one interests me I'll go off and
read that article, but eventually return to my page. When I choose another
value from the drop-down, I do an auto-postback, and refresh the list of
articles below.

All works well unless the page is left idle for a period of time. If I then
return and select another value from the drop-down list, I'll often receive
an error "The Viewstate is invalid for this page and might be corrupted." My
application runs with <sessionState>O ff</sessionState>.

My site runs on a web hosting company, and they have informed me that the
problem exists only under Windows 2003, with "worker process recycling" in
effect, and with a site with "minimal traffic", i.e. one where the worker
process is recycled between page postbacks. My questions are:

1. Why should "worker process recycling" cause the viewstate value posted
back from my form to be considered invalid or corrupt?
2. Is this a known issue with Windows 2003?
3. Would providing an overloaded version of the
LoadPageStateFr omPersistenceMe dium method be a good approach to solve the
problem?

Any feed back on these questions or relevant related topics would be very,
very much appreciated.

Regards,
Trevor Andrew