asp.net app losing session

I have an asp.net app that has many frames and is quite intensive.

One of the iframes refreshes every 30 seconds to update user's data, now this page should also keep the users session active.

I have also tried using cookieless sessions, so the session is munged in the URL, but sometimes the session variables are still lost. i.e sometimes the iframe refreshes itself and it no longer contains any data for the session varialble.

There are no records in the event log of the aspnet_wp stopping unexpectedly, so how can this happen?

tbh you should avoid use of the sessionless cookie state and especially in frames as it will create a different session for each page I think

If you're rebuilding your project, that'll reset session states. If aspnet_wp stops you'll know about it with bid red writing lol :-)

Also I have seen a lot of problems related to sessions when using frames like this.

I'd get rid of the evil frames :-P