Most elements of an ASP.NET page are not rendered after random idle time

Question

We have been trying to figure this one out for a while now, without any luck.

The symptoms are as follows:

• After some idle time of a specific ASP.NET 2.0 application (can be from several hours to days), one of the pages in my application stops working.
• When viewing the source of the page I see many elements missing, elements that are usually there, such as: reference to WebResource.axd, the __doPostBack() function, all of the UserControls and more.
• A reference to ScriptResource.axd, and the __VIEWSTATE are there.
• After recycling the app pool, the application starts working correctly again and everything renders well.
• This only happens on a specific server, when deploying the same application on a different server, this error does not occur.

The page that the error occurs on has only one UserControl which is not rendered when the error occurs. Nothing special happens when this page is loaded.

We tried doing periodic client refreshes, but that did not help either.

Thanks in advance.

Answer 1

It was a caching issue. There was a part in the code that hid specific controls when the cache was invalid. That explains the missing code parts.

I am still not sure why the cache was invalid on that specific server.