Yes you can
Because all the configuration settings will be
available under MACHINE.CONFIG file by default these settings will be applied
to all asp.net applications. The MACHINE.CONFIG file will be automitacally
loaded when .net framework is installed.
it is something like if we had not defined the
web.config the application will take the settings from the
machine.config. the machine.config settings are overide by the web.config
if u define the web.config for each running application.
In 2005 The VS When we trying to run first time any
application the 2005 VS gives us warning that want to run application without web.config
file.