Unable to launch the IIS Express Web server

Failed to register URL “http://localhost:63647” for site application. Error description: The process cannot access the file because it is being used by another process (0x80070020).

1. Open project properties.
2. Choose “Web” on the left hand side.
3. Update the port number in the project URL. Then click yes if you want to update the virtual directory.
VisualStudio_Project URL

4. Save and restart Visual studio, then you should be good to go! =)


Section is locked (ipSecurity configuration)

Module IpRestrictionModule
Notification BeginRequest
Handler ExtensionlessUrl-Integrated-4.0
Error Code 0x80070021
Config Error This configuration section cannot be used at this path. This happens when the section is locked at a parent level. Locking is either by default (overrideModeDefault=”Deny”), or set explicitly by a location tag with overrideMode=”Deny” or the legacy allowOverride=”false”.

Update file: applicationhost.config (%userprofile%\documents\iisexpress\config\applicationhost.config)

Change line:
<section name=”ipSecurity” overrideModeDefault=”Deny” />

<section name=”ipSecurity” overrideModeDefault=”Allow” />

And in web.config use:

<ipSecurity allowUnlisted=”false” denyAction=”Unauthorized”>
<add ipAddress=”X.X.X.X” allowed=”true” subnetMask=”″ />

Local IIS failed to map the path ‘/’

Got an exception of System.InvalidOperationException: “Failed to map the path ‘/'” when starting the site on a local IIS.

System.Web.HttpRuntime.HostingInit(HostingEnvironmentFlags hostingFlags, PolicyLevel policyLevel, Exception appDomainCreationException) +556

[HttpException (0x80004005): Det gick inte att mappa sökvägen /.]
System.Web.HttpRuntime.FirstRequestInit(HttpContext context) +579
System.Web.HttpRuntime.EnsureFirstRequestInit(HttpContext context) +118
System.Web.HttpRuntime.ProcessRequestNotificationPrivate(IIS7WorkerRequest wr, HttpContext context) +730

With my modest knowledge about hosting a site on a local IIS the solution turned out to be really simple.

1. Start a new command prompt in administrator mode.
2. Run command: “iisreset”