If IE is failing to find the content then it looks like a failure in contact with that database.
I use Internet Explorer in kiosk mode to display content on a screen. The display is on a single webpage which refreshes regularly to display different messages pulled from a database. Everything runs fine for around 6 hours then for no obviuos reason Explorer says the website can not be found. There is no problem with the internet connection.
The really strange part is that if I then close the browser and re-open it in non-kiosk mode it still won't display the page. If I then navigate to some other page (eg Google) and then go back to the page I want to display everything works fine. It's as if Explorer has got bored and is refusing to display the page I want until I let it go to some other website and then back again.
This all happens with different versions of explorer and on machines running XP and Windows 7. Anyone got any ideas?