Wierd Error if page is left alone for too long... (ajax pages)

I have a wierd error that only occours if there has been no interaction with the webserver for too long. (over 30 mins)

The specific error that is returned is

Sys.WebForms.PageRequestManagerServerErrorException: An unknown error occoured while processing the request on the server. The status code returned from the server was: 504

This seems to happen to any page that has a script manager and update panel in it. I have tried adjusting the session timeout period, but this doesn't seem to help. It is almost like the page is loosing it's reference to the script files required by the ScriptManager. Is there some caching parameter I could add to the page to extend the cache time?

Any other ideas are welcome. This is a strange one. So far the workaround is to add a timer to the page that just keeps it alive.. (updates the page every minute or so with a meaningless value...)

TIA

Rob

See:http://forums.asp.net/p/1134743/1809108.aspx#1809108

-Damien

Hi,

Please see this post:504 Gateway Timeout occuring for very small number of users

504 Gateway Timeout
The server, while acting as a gateway or proxy, did not receive a timely response from the upstream server it accessed in attempting to complete the request.

Best Regards