Thank you in advance.

My ASP page 1 redirect user to third party's website,
after the process at third party is finished, in 3rd
party's page, there is one link to route user back to my
website: ASP page2.

As the user do all of these actions in the same browser, I
expect the user's session variables to be kept, But the
seesion variable are lost.

What is wrong?

Alex

IIS will only keep a session alive if the browser is requesting asp pages
from it. When you view a third party site for longer than the session
timeout then the session is destroyed as there has been to request to it
within the timeout.

There are some tricks you can do to keep a session alive. You could put the
third party site in a frameset where the main frame is the site and there is
a small frame on the top of the page that refreshes itself every 5 mins or
so. The refresh keeps the session on your site alive while the user
browsers the third party site in the frame.

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