ASP COM Plus <comPlus>

Overview

The <comPlus> element of the <asp> element configures the following COM+ settings for Active Server Pages (ASP) in Internet Information Services (IIS) 7:

  • The appServiceFlags property contains the flags that must be set to enable COM+ services on your IIS 7 applications. Once you enable the flags, you may also need to set other properties. For more information, see the Configuration Details section later in this topic.
  • The executeInMta attribute specifies whether ASP can run scripts in a multithreaded apartment. ASP is capable of running all of its threads in a multi-threaded apartment (MTA). If your COM components are primarily free-threaded or both-threaded, running the ASP threads as MTA can improve performance significantly. By default, the executeInMta property is set to false, which means that ASP does not execute in MTA. Set this property to true at the application level to enable ASP to run in MTA.
  • The partitionId attribute specifies the Globally Unique Identifier (GUID) of a COM+ partition, which is used to isolate Web applications into their own COM+ partitions. COM+ partitions hold different versions of your own custom COM components.

    Note: If you specify a value for the partitionId attribute, you will also need to set the UsePartition flag of the appServiceFlags attribute.
  • The sxsName attribute specifies the name of a COM+ application, and enables side-by-side (SxS) assemblies. Side-by-side (SxS) assemblies allow ASP applications to specify which version of an SxS-supported system DLL to use, such as MSVCRT, MSXML, COMCTL, GDIPLUS, and so on.

    Note: If you specify a value for the sxsName attribute, you will also need to set the EnableSxS flag of the appServiceFlags attribute.
  • The trackThreadingModel attribute specifies whether IIS 7 checks the threading model of any components (COM objects) that your application creates. The preferred setting of this metabase attribute is false. If trackThreadingModel is set to true the following conditions apply:
    • ASP uses system resources to track the threading model, reducing the performance of your ASP application.
    • Objects that are created in your ASP application outside of the OnStartPage or OnEndPage method are released earlier than expected, which causes degradation in the scalability of your application and can prevent your component from writing to the response in the object destructor method.

    If the trackThreadingModel attribute is set to false, and you give application scope to components that you create, those components must aggregate the free-threaded marshaler. If you do not aggregate the free-threaded marshaler, ASP generates an error when you try to create an instance of the component. For more information, see Selecting a Threading Model for Components in IIS in the Platform SDK.

Compatibility

Version Notes
IIS 8.5 The <comPlus> element was not modified in IIS 8.5.
IIS 8.0 The <comPlus> element was not modified in IIS 8.0.
IIS 7.5 The <comPlus> element was not modified in IIS 7.5.
IIS 7.0 The <comPlus> element of the <asp> element was introduced in IIS 7.0.
IIS 6.0 The <comPlus> element replaces the following IIS 6.0 metabase properties:
  • AspAppServiceFlags
  • AspExecuteInMTA
  • AspPartitionID
  • AspSxsName
  • AspTrackThreadingModel

Setup

To support and configure ASP applications on your Web server, you must install the ASP module. To install the ASP module, use the following steps.

Windows Server 2012 or Windows Server 2012 R2

  1. On the taskbar, click Server Manager.
  2. In Server Manager, click the Manage menu, and then click Add Roles and Features.
  3. In the Add Roles and Features wizard, click Next. Select the installation type and click Next. Select the destination server and click Next.
  4. On the Server Roles page, expand Web Server (IIS), expand Web Server, expand Application Development, and then select ASP.
    .
  5. If the Add features that are required by ASP? dialog box appears, click Add Features. (This page appears only if you have not already installed the ISAPI Extensions role service on your server.)
  6. On the Server Roles page, click Next.
  7. On the Select features page, click Next.
  8. On the Confirm installation selections page, click Install.
  9. On the Results page, click Close.

Windows 8 or Windows 8.1

  1. On the Start screen, move the pointer all the way to the lower left corner, right-click the Start button, and then click Control Panel.
  2. In Control Panel, click Programs and Features, and then click Turn Windows features on or off.
  3. Expand Internet Information Services, expand World Wide Web Services, expand Application Development Features, and then select ASP.

    Note: The ISAPI Extensions role will be selected if it has not already been installed.
  4. Click OK.
  5. Click Close.

Windows Server 2008 or Windows Server 2008 R2

  1. On the taskbar, click Start, point to Administrative Tools, and then click Server Manager.
  2. In the Server Manager hierarchy pane, expand Roles, and then click Web Server (IIS).
  3. In the Web Server (IIS) pane, scroll to the Role Services section, and then click Add Role Services.
  4. On the Select Role Services page of the Add Role Services Wizard, select ASP.

  5. If the Add role services required by ASP dialog box appears, click Add Required Role Services. (This page appears only if you have not already installed the ISAPI Extensions role service on your server.)

  6. On the Select Role Services page, click Next.
  7. On the Confirm Installation Selections page, click Install.
  8. On the Results page, click Close.

Windows Vista or Windows 7

  1. On the taskbar, click Start, and then click Control Panel.
  2. In Control Panel, click Programs and Features, and then click Turn Windows Features on or off.
  3. Expand Internet Information Services, then World Wide Web Services, then Application Development Features.
  4. Select ASP, and then click OK.

How To

How to configure ASP session state settings for a site or application

  1. Open Internet Information Services (IIS) Manager:
    • If you are using Windows Server 2012 or Windows Server 2012 R2:
      • On the taskbar, click Server Manager, click Tools, and then click Internet Information Services (IIS) Manager.
    • If you are using Windows 8 or Windows 8.1:
      • Hold down the Windows key, press the letter X, and then click Control Panel.
      • Click Administrative Tools, and then double-click Internet Information Services (IIS) Manager.
    • If you are using Windows Server 2008 or Windows Server 2008 R2:
      • On the taskbar, click Start, point to Administrative Tools, and then click Internet Information Services (IIS) Manager.
    • If you are using Windows Vista or Windows 7:
      • On the taskbar, click Start, and then click Control Panel.
      • Double-click Administrative Tools, and then double-click Internet Information Services (IIS) Manager.
  2. In the Connections pane, expand the server name, expand Sites, and then navigate to the Web site or Web application that you want to configure.
  3. In the site or application Home pane, double-click ASP.

  4. In the ASP pane, expand the Com Plus Properties section and configure your desired settings.

  5. Click Apply in the Actions pane.

Configuration

Attributes

Attribute Description
appServiceFlags Optional flags attribute.

Contains the flags that must be set to enable COM+ services on your IIS applications.

The appServiceFlags attribute can be one of the following possible values. The default value is None.
Value Description
None Specifies that no flags are set.

The numeric value is 0.
EnableTracker Setting this flag enables COM+ tracker, which allows administrators or developers to debug ASP applications.

The numeric value is 1.
EnableSxS Setting this flag enables COM+ side-by-side assemblies, which allow ASP applications to specify which version of a system DLL or classic COM component to use, such as WinHTTP 5.1, Shell Common Controls version 6.0 (Comctl32.dll), GDI Plus version 1.0 (GDIplus.dll), and Visual C++ Run-time Libraries version 6.0. If this flag is set, you must also specify a value for the sxsName attribute.

The numeric value is 2.
UsePartition Setting this flag enables COM+ partitioning, which can be used to isolate Web applications into their own COM+ partitions. COM+ partitions can hold different versions of your own custom COM components. If this flag is set, you must also specify a value for the partitionId attribute.

The numeric value is 4.
executeInMta Optional Boolean attribute.

Specifies whether ASP runs in a multithreaded environment.

The default value is false.
partitionId Optional string attribute.

Specifies the Globally Unique Identifier (GUID) of the COM+ partition.

Note: This attribute is required when the appServiceFlags attribute is set to UsePartition

The default value is 00000000-0000-0000-0000-000000000000.
sxsName Optional string attribute.

Note: This attribute is required when the appServiceFlags attribute is set to EnableSxS.

Specifies the name of the COM+ application.
trackThreadingModel Optional Boolean attribute.

Specifies whether thread model checking is enabled. A value of true means that IIS honors the threading model of the components that an application creates.

The default value is false.

Child Elements

None.

Configuration Sample

The following configuration sample shows how to configure IIS to enable thread model checking and configure ASP to run in a multithreaded compartment.

<configuration>
   <system.webServer>
      <asp>
         <comPlus trackThreadingModel="true" executeInMta="true" />
      </asp>
   </system.webServer>
</configuration>

Sample Code

The following code samples show how to configure IIS to enable thread model checking and configure ASP to run in a multithreaded compartment.

AppCmd.exe

appcmd.exe set config "Default Web Site" -section:system.webServer/asp /comPlus.trackThreadingModel:"True" /commit:apphost
appcmd.exe set config "Default Web Site" -section:system.webServer/asp /comPlus.executeInMta:"True" /commit:apphost

Note: You must be sure to set the commit parameter to apphost when you use AppCmd.exe to configure these settings. This commits the configuration settings to the appropriate location section in the ApplicationHost.config file.

C#

using System;
using System.Text;
using Microsoft.Web.Administration;

internal static class Sample
{
   private static void Main()
   {
      using (ServerManager serverManager = new ServerManager())
      {
         Configuration config = serverManager.GetApplicationHostConfiguration();
         ConfigurationSection aspSection = config.GetSection("system.webServer/asp", "Default Web Site");

         ConfigurationElement comPlusElement = aspSection.GetChildElement("comPlus");
         comPlusElement["trackThreadingModel"] = true;
         comPlusElement["executeInMta"] = true;

         serverManager.CommitChanges();
      }
   }
}

VB.NET

Imports System
Imports System.Text
Imports Microsoft.Web.Administration

Module Sample

   Sub Main()
      Dim serverManager As ServerManager = New ServerManager
      Dim config As Configuration = serverManager.GetApplicationHostConfiguration
      Dim aspSection As ConfigurationSection = config.GetSection("system.webServer/asp", "Default Web Site")

      Dim comPlusElement As ConfigurationElement = aspSection.GetChildElement("comPlus")
      comPlusElement("trackThreadingModel") = True
      comPlusElement("executeInMta") = True

      serverManager.CommitChanges()
   End Sub

End Module

JavaScript

var adminManager = new ActiveXObject('Microsoft.ApplicationHost.WritableAdminManager');
adminManager.CommitPath = "MACHINE/WEBROOT/APPHOST";

var aspSection = adminManager.GetAdminSection("system.webServer/asp", "MACHINE/WEBROOT/APPHOST/Default Web Site");
var comPlusElement = aspSection.ChildElements.Item("comPlus");
comPlusElement.Properties.Item("trackThreadingModel").Value = true;
comPlusElement.Properties.Item("executeInMta").Value = true;

adminManager.CommitChanges();

VBScript

Set adminManager = WScript.CreateObject("Microsoft.ApplicationHost.WritableAdminManager")
adminManager.CommitPath = "MACHINE/WEBROOT/APPHOST"

Set aspSection = adminManager.GetAdminSection("system.webServer/asp", "MACHINE/WEBROOT/APPHOST/Default Web Site")
Set comPlusElement = aspSection.ChildElements.Item("comPlus")
comPlusElement.Properties.Item("trackThreadingModel").Value = True
comPlusElement.Properties.Item("executeInMta").Value = True

adminManager.CommitChanges()
Deprecated Elements