Web Browser Control stops requesting web server after prolonged us
Tory McKeag
I'm supporting an enterprise intranet-scope web application in production,
and it is used two different ways:
1. About 90% of the users access the application randomly throughout the
day, either with directly with the IE browser (IE 6 SP2), or with an
application that wraps the web browser control with C# code (the .NET 1.1
way...)
2. About 10% of the users, considered the more critical by the customer,
access the application continuously, 24 by 7 by 365, via the application that
wraps the web browser via C# code. I think it is important to note that this
"super client" application does a number of other things, and is essentially
the user's portal to controlling their environment at work. There is also a
feature to change their user at shift change. The result is that this client
application potentially stays up for weeks at a time.
The problem is specifically with user group #2. On certain machines, the
users will eventually get HTTP 404 error screens trying to access the web
application after some period of use. However, as far as I can tell, the
server isn't getting any HTTP requests. If I open an IE browser on the
machine while this is happening, it gets to the web app just fine. The
problem is resolved if the users restart their client application containing
the web browser control. There was a period where these users used the web
application in just the web browser, and not this client app, which leads me
to believe this is some issue with the web browser control, but I'm not sure.
For all I know it could be problems with the customer's firewalls/network
config etc.
Any ideas? Where could I start? HTTP headers? Network settings? Is there
some internal cache in the browser control I need to clear?
Igor Tandetnik
> The problem is specifically with user group #2. On certain machines,
> the users will eventually get HTTP 404 error screens trying to access
> the web application after some period of use. However, as far as I
> can tell, the server isn't getting any HTTP requests. If I open an
> IE browser on the machine while this is happening, it gets to the web
> app just fine. The problem is resolved if the users restart their
> client application containing the web browser control.
Everybody trying to use IE in any kind of kiosk application seems to
encounter this problem. Apparently, there are memory and/or some other
resource leaks in IE, that make it unstable after prolonged use. The
only soluton seems to be to recycle (shut down and restart) the whole
process: simply destroying and recreating WebBrowser instance doesn't
help.
Can't you automatically shut down and restart on shift change, for
example?
--
With best wishes,
Igor Tandetnik
With sufficient thrust, pigs fly just fine. However, this is not
necessarily a good idea. It is hard to be sure where they are going to
land, and it could be dangerous sitting under them as they fly
overhead. -- RFC 1925