When you get this error it means that there's probably something broken in your site's
web.config file. IIS7 is very helpful in these cases and will usually point you roughly where the problem lies.
For example, I've deliberately broken a
web.config on a test site by making it malformed XML:
The areas highlighted in red are providing me with a hint as to what is broken.
Without seeing the full error message from your site it would be hard to speculate what is wrong other than that something is invalid in your
web.config file (or perhaps a parent
Based on your update and the new screenshot comment out the line indicated in red in your
web.config file, e.g.:
<!-- <modules runAllManagedModulesForAllRequests="true"/> -->
It looks like this setting has been locked somewhere on your machine, probably in the
applicationHost.config file in
You could try unlocking this setting to allow the
web.config setting to be used by running the following on an Administrator command line:
appcmd.exe unlock config /section:system.webserver/modules /commit:apphost