Information associated with IIS site isn't deleted during programmatic site deletion

This article helps you resolve the problem where information associated with IIS site isn't deleted during programmatic site deletion.

Original product version:   Internet Information Services 8.0, Internet Information Services 8.5
Original KB number:   3202096

Symptoms

Consider the following scenario:

• You delete a site by using calls to appcmd or to the managed APIs that are exposed by Microsoft.Web.Administration binary.
• You create a new site in Internet Information Services (IIS) 7.5 or later versions.
• The new site still uses the legacy metadata of the deleted site.

In this scenario, unexpected behavior occurs when you try to access the newly created site. For example, you may receive an HTTP 503 - Service Unavailable error message in your web browser.

Cause

The problem occurs when a delete operation for an existing website in IIS is performed programmatically by using appcmd or Microsoft.Web.Administration APIs and if the site has legacy properties defined in the <CustomMetaData> configuration element of the ApplicationHost.config file of the IIS server. The information in the <CustomMetaData> tag that's relevant to the site is not deleted in this scenario. If a new site with the same ID is created after the delete operation, this new site will be associated with the legacy properties of the old site.

Resolution

You can use the IIS Administration Console to delete the website instead of making calls to appcmd or Microsoft.Web.Administration. This method makes sure that if there are any custom legacy properties associated with the website you're trying to delete, they will also be deleted from the IIS configuration file (ApplicationHost.config). This will prevent these properties from being unexpectedly associated with a new website that you create on the same server that reuses the ID of the old deleted site.

If you must delete the site programmatically for any reason and cannot use the IIS Manager Console, you can add either of the two workarounds to make sure that the information on the legacy properties that's associated with the site through the <CustomMetaData> element is also deleted.

Workaround 1: Use appcmd commands

If you are using appcmd to delete the site, you can then run the following command to remove any legacy properties that the site may have had in the IIS configuration:

Appcmd clear config -section:customMetadata -[path='LM/W3SVC/<SiteID>']

Workaround 2: Use calls to Microsoft.Web.Administration

If you are using managed API calls to Microsoft.Web.Administration to delete the website, you can add the following code after the website has been deleted to also clear the legacy properties contained in the <CustomMetaData> element of the IIS configuration:

string path = "LM/W3SVC/" + site.Id.ToString(CultureInfo.InvariantCulture);
string pathWithSlash = path + "/";
for (int i = customMetadata.Count - 1; i >= 0; i--) {
    ConfigurationElement metadata = customMetadata[i];
    string key = (string)metadata["path"];
    if (key != null &&
    (
        key.Equals(path, StringComparison.OrdinalIgnoreCase) || 
        key.StartsWith(pathWithSlash, StringComparison.OrdinalIgnoreCase))
    ) 
    {
        customMetadata.RemoveAt(i);
    }
}

Steps to reproduce

On a Windows 2008 R2 / IIS 7.5 or a Windows 2012 R2 / IIS 8.5 Server:

1. Install the IIS 6 metabase compatibility feature.

2. In the IIS manager, create a second website: call this WebTest and make it run on any application pool desired.

3. Open a command line prompt and navigate to: C:\inetpub\AdminScripts.

4. Type in the following command: adsutil.vbs SET w3svc/2/ServerSize "23".

   This will add the following section to the W3SVC tag in the ApplicationHost.config file:

   <customMetadata>
   ....
   <key path="LM/W3SVC/2">
   <property id="1018" dataType="DWord" userType="1" attributes="Inherit" value="23" />
   </key>
   ....
   </customMetadata>
   

5. Now navigate to the C:\windows\system32\inetsrv\ inside the command prompt.

6. Run the command: appcmd delete site WebTest.

7. After the site is deleted, the above section of configuration is still present in ApplicationHost.config.