FIX: "ASP.NET Apps v2.0.50727(__Total__)\Sessions Active" performance counter shows an unreasonably high value after Microsoft .NET Framework 3.5 Service Pack 1 is installed

Consider the following scenario:

• You have installed Microsoft .NET Framework 3.5 Service Pack 1 (SP1).
• You use System Monitor (PerfMon) to monitor the performance of running ASP.NET applications.

In this situation, you may notice that the performance counter "ASP.NET Apps v2.0.50727(__Total__)\Sessions Active" sometimes shows an unreasonably high value. For example, the value that is shown is 4294967267.

Note The Sessions Active counter indicates the number of sessions currently active. For more information about how to monitor ASP.NET applications by using PerfMon, see the "More information" section.

A supported hotfix is now available from Microsoft. However, it is intended to correct only the problem that is described in this article. Apply it only to systems that are experiencing this specific problem. This hotfix may receive additional testing. Therefore, if you are not severely affected by this problem, we recommend that you wait for the next service pack that contains this hotfix.

To resolve this problem immediately, contact Microsoft Customer Support Services to obtain the hotfix. For a complete list of Microsoft Customer Support Services telephone numbers and information about support costs, visit the following Microsoft Web site:Note In special cases, charges that are ordinarily incurred for support calls may be canceled if a Microsoft Support Professional determines that a specific update will resolve your problem. The usual support costs will apply to additional support questions and issues that do not qualify for the specific update in question.

Prerequisites

You must have Microsoft .NET Framework 3.5 Service Pack 1 (SP1) installed to apply this hotfix. You must apply this hotfix on Windows XP and Windows Server 2003.

Restart requirement

You may have to restart the computer after you apply this hotfix if any of the affected files are being used when you install it. Shutting down any ASP.NET Web site before installing the fix should enable you to avoid having to restart the system.

Hotfix replacement information

This hotfix does not replace any other hotfixes.

File information

The English version of this hotfix has the file attributes (or later file attributes) that are listed in the following table. The dates and times for these files are listed in Coordinated Universal Time (UTC). When you view the file information, it is converted to local time. To find the difference between UTC and local time, use the Time Zone tab in the Date and Time item in Control Panel.

Windows XP and Windows Server 2003, x86-based version

Windows XP and Windows Server 2003, x64-based version

Windows Server 2003, IA-64 based version

Microsoft has confirmed that this is a problem in the Microsoft products that are listed in the "Applies to" section.

For more information about ASP.NET Performance Monitoring, visit the following Microsoft web site: In some cases, after you install this fix, when you try to access the ASP.NET Performance counters by using Windows Management Instrumentation (WMI), the counters may have values of 0. Or, there may be no counter instances listed.

For example, this issue may occur when you try to access the ASP.NET Performance counters by starting PERFMON with the /WMI switch or by using Microsoft Operations Manager (MOM) or Systems Center Operations Manager (SCOM).

Microsoft are still investigating this issue. However, you can use the following procedure to workaround this issue:

1. Open Wbemtest.exe
2. Connect to the root\cimv2 namespace.
3. Delete the Win32_PerfRawData_ASPNET_2050727_ASPNETAppsv2050727 class.
4. Winmgmt /resyncperf
5. Net stop winmgmt
6. Net start winmgmt

For more information, see the following MSDN blog post: