When a client attempts to connect to a Microsoft Internet
Information Services (IIS) application that is restarting, the browser displays
the following error message:
The page cannot be displayed There is a problem with the page you are trying to reach and it
cannot be displayed.
HTTP Error 500-12 Application Restarting
Internet Information Services
This message is harmless and usually disappears after the
browser is refreshed. There is no good workaround once the message appears from
a production environment. However, if the message appears for an extended
period of time, you may want to consider stopping all the Web services and
reloading the application.
When certain changes are made to an IIS 5.0 application,
those changes are committed to the Global.asa file for the application. When
you save changes to the Global.asa file, the server finishes processing all of
the current application requests before it recompiles the Global.asa file.
During that time, the server refuses additional requests and returns an error
message stating that the request cannot be processed while the Web site is
After all of the current user requests have been
processed, the server deletes all active sessions, calling the Session_OnEnd
event for each session it deletes, closes the application, and then calls the
Application_OnEnd event. The Global.asa file is then recompiled.
Subsequent user requests will start the application and create new sessions,
and trigger the Application_OnStart and Session_OnStart events. When you view
an ASP page while the application is running Application_OnStart, the following
error message occurs:
HTTP Error 500-12 Application
The message is harmless and usually disappears when you
refresh the page in your browser.
This error message may also be
caused by anti-virus or backup software. When these software packages scan an
IIS Web application, IIS may behave as if the Global.asa file has been modified
and may therefore restart the Web application. Turning off backup software and
virus scanning on the Global.asa file may help resolve this issue. If a client
GET request is made during this time, the web server will return a 500-12
For additional information on
the same error message occurring in Site Server 3.0, Commerce Edition, click
the article number below to view the article in the Microsoft Knowledge Base:
Err Msg: HTTP 1.1 Application Restarting