I've been debugging an issue we have in an asp.net 2.0 application for\nseveral days.\n\nThe initial report of the bug was that, after waiting for some minutes with\nan open page, entering a number in a search box and clicking the\ncorresponding button, the page came empty.\nEntering the data again and clicking the button always gives results.\n\nI wrote a "request sniffer" module that writes a log for all requests that\nincludes the time, method, url, IsPostBack, referer, server ip and body\ncontents (I'm willing to share it - just ask)\nUsing it, I was able to determine that IsPostBack is returning false when\nthis happens, regardless of the Request.Form collection having post data.\n\nSome more information:\n- This happens in a web farm. My initial analysis showed that the error\nhappened when a different server answered. But later I reproduced it with the\nsame server\n- We're using SiteMinder, a SSO agent implemented in ISAPI. However, this\nappears not to be the cause\n- The site is located in a network share. This required changes to the .NET\nsecurity policies. Also, besides having supposedly configured the machineKey\nin all the boxes, I had to disable viewStateEncryption and enableViewStateMac\nsome time ago\n- The error appears in a completely erratic way; I haven't found a\nreproduction pattern yet. I have another development server (not a web farm)\nwhere the error hasn't been reproduced\n\nAll help with this will be greatly appreciated.\nWhen suggesting things to test, keep in mind that I'm NOT the server\nadministrator (I only have file share access to the website root). The web\nfarm runs several corporate sites and it can't be happily restarted or have\nits global configuration changed without a good reason.