Symptoms
Consider the following scenario in a network environment:
A web service is hosted on a computer that is running one of the following operating systems:
- Windows Vista
- Windows Server 2008
- Windows 7
- Windows Server 2008 R2
For example, Internet Information Services (IIS) or an application that uses the System.Net.HttpListener class is installed.
A network load balancer is deployed in the network environment.
Some clients send HTTP requests to the computer by using the TLS/SSL protocol.
In this scenario, new HTTP client requests may be delayed. Additionally, clients may receive errors when they try to access the web service.
Note The HTTP protocol stack (Http.sys) is used on the computer to receive HTTP requests from clients.
Cause
The issue occurs because some HTTP requests from clients may include zero-length data in their SSL records. These zero-length data records cause certain server-side variables not to update correctly. If a client closes their connection to the web service and the last packet that was sent contained a zero-length data record, then Http.sys cannot adjust certain necessary variables. Therefore, Http.sys leaves the connection in the CLOSE_WAIT state. With time, the computer may reach its open connection limit. When this occurs, no new connections are accepted by the computer.
Note The CLOSE_WAIT state indicates a passive close. Specifically, it indicates that the server has only received the first FIN flag from a client.
Resolution
Hotfix information
A supported hotfix is available from Microsoft. However, this hotfix is intended to correct only the problem that described in this article. Apply this hotfix only to systems that are experiencing the problem described in this article. This hotfix might receive additional testing. Therefore, if you are not severely affected by this problem, we recommend that you wait for the next software update that contains this hotfix.
If the hotfix is available for download, there is a "Hotfix download available" section at the top of this Knowledge Base article. If this section does not appear, contact Microsoft Customer Service and Support to obtain the hotfix.
Note If additional issues occur or if any troubleshooting is required, you might have to create a separate service request. The usual support costs will apply to additional support questions and issues that do not qualify for this specific hotfix. For a complete list of Microsoft Customer Service and Support telephone numbers or to create a separate service request, visit the following Microsoft website:
http://support.microsoft.com/contactus/?ws=support Note The "Hotfix download available" form displays the languages for which the hotfix is available. If you do not see your language, it is because a hotfix is not available for that language.
Prerequisites
To apply this hotfix, you must be running one of the following operating systems:
- Windows Vista Service Pack 2 (SP2)
- Windows Server 2008 Service Pack 2 (SP2)
- Windows 7 Service Pack 1 (SP1)
- Windows Server 2008 R2 Service Pack 1 (SP1)
For more information about how to obtain a Windows Vista service pack, click the following article number to view the article in the Microsoft Knowledge Base:
935791 How to obtain the latest Windows Vista service pack
For more information about how to obtain a Windows Server 2008 service pack, click the following article number to view the article in the Microsoft Knowledge Base:
968849 How to obtain the latest service pack for Windows Server 2008
For more information about how to obtain a Windows 7 or a Windows Server 2008 R2 service pack, click the following article number to view the article in the Microsoft Knowledge Base:
976932 Information about Service Pack 1 for Windows 7 and for Windows Server 2008 R2
Registry information
To use the hotfix in this package, you do not have to make any changes to the registry.
Restart requirement
You must restart the computer after you apply this hotfix.
Hotfix replacement information
This hotfix does not replace a previously released hotfix.
File information
The global version of this hotfix installs files that have the attributes that are listed in the following tables. The dates and the times for these files are listed in Coordinated Universal Time (UTC). The dates and the times for these files on your local computer are displayed in your local time together with your current daylight saving time (DST) bias. Additionally, the dates and the times may change when you perform certain operations on the files.
Windows Vista and Windows Server 2008 file information notes
Important Windows Vista hotfixes and Windows Server 2008 hotfixes are included in the same packages. However, only "Windows Vista" is listed on the Hotfix Request page. To request the hotfix package that applies to one or both operating systems, select the hotfix that is listed under "Windows Vista" on the page. Always refer to the "Applies To" section in articles to determine the actual operating system that each hotfix applies to.
The files that apply to a specific product, SR_Level (RTM, SPn), and service branch (LDR, GDR) can be identified by examining the file version numbers as shown in the following table.
Version Product SR_Level Service branch 6.0.600
2.
22xxxWindows Vista and Windows Server 2008 SP2 LDR The MANIFEST files (.manifest) and the MUM files (.mum) that are installed for each environment are listed separately in the "Additional file information for Windows Server 2008 and for Windows Vista" section. MUM files and MANIFEST files, and the associated security catalog (.cat) files, are extremely important to maintain the state of the updated components. The security catalog files, for which the attributes are not listed, are signed with a Microsoft digital signature.
For all supported x86-based versions of Windows Server 2008 and of Windows Vista
| File name | File version | File size | Date | Time | Platform |
|---|---|---|---|---|---|
| Httpapi.dll | 6.0.6002.22730 | 30,720 | 21-Oct-2011 | 16:50 | x86 |
| Http.sys | 6.0.6002.22730 | 413,696 | 21-Oct-2011 | 14:22 | x86 |
For all supported x64-based versions of Windows Server 2008 and of WindowsVista
| File name | File version | File size | Date | Time | Platform |
|---|---|---|---|---|---|
| Httpapi.dll | 6.0.6002.22730 | 33,792 | 21-Oct-2011 | 16:03 | x64 |
| Http.sys | 6.0.6002.22730 | 620,032 | 21-Oct-2011 | 14:21 | x64 |
| Httpapi.dll | 6.0.6002.22730 | 30,720 | 21-Oct-2011 | 16:50 | x86 |
For all supported IA-64-based versions of Windows Server 2008
| File name | File version | File size | Date | Time | Platform |
|---|---|---|---|---|---|
| Httpapi.dll | 6.0.6002.22730 | 70,656 | 21-Oct-2011 | 16:09 | IA-64 |
| Http.sys | 6.0.6002.22730 | 1,184,256 | 21-Oct-2011 | 14:48 | IA-64 |
| Httpapi.dll | 6.0.6002.22730 | 30,720 | 21-Oct-2011 | 16:50 | x86 |
Windows 7 and Windows Server 2008 R2 file information notes
Important Windows 7 hotfixes and Windows Server 2008 R2 hotfixes are included in the same packages. However, hotfixes on the Hotfix Request page are listed under both operating systems. To request the hotfix package that applies to one or both operating systems, select the hotfix that is listed under "Windows 7/Windows Server 2008 R2" on the page. Always refer to the "Applies To" section in articles to determine the actual operating system that each hotfix applies to.
The files that apply to a specific product, SR_Level (RTM, SPn), and service branch (LDR, GDR) can be identified by examining the file version numbers as shown in the following table.
Version Product SR_Level Service branch 6.1.760
1.
21xxxWindows 7 and Windows Server 2008 R2 SP1 LDR The MANIFEST files (.manifest) and the MUM files (.mum) that are installed for each environment are listed separately in the "Additional file information for Windows Server 2008 R2 and for Windows 7" section. MUM and MANIFEST files, and the associated security catalog (.cat) files, are extremely important to maintain the state of the updated components. The security catalog files, for which the attributes are not listed, are signed with a Microsoft digital signature.
For all supported x86-based versions of Windows 7
| File name | File version | File size | Date | Time | Platform |
|---|---|---|---|---|---|
| Http.sys | 6.1.7601.21866 | 514,048 | 24-Nov-2011 | 04:07 | x86 |
For all supported x64-based versions of Windows 7 and of Windows Server 2008 R2
| File name | File version | File size | Date | Time | Platform |
|---|---|---|---|---|---|
| Http.sys | 6.1.7601.21866 | 753,152 | 24-Nov-2011 | 04:21 | x64 |
For all supported IA-64-based versions of Windows Server 2008 R2
| File name | File version | File size | Date | Time | Platform |
|---|---|---|---|---|---|
| Http.sys | 6.1.7601.21866 | 1,443,328 | 24-Nov-2011 | 03:18 | IA-64 |
Status
Microsoft has confirmed that this is a problem in the Microsoft products that are listed in the "Applies to" section.
More Information
For more information about software update terminology, click the following article number to view the article in the Microsoft Knowledge Base:
824684 Description of the standard terminology that is used to describe Microsoft software updates
Additional file information
Additional file information for Windows Vista and for Windows Server 2008
Additional files for all supported x86-based versions of Windows Vista and of Windows Server 2008
| File name | Update.mum |
|---|---|
| File version | Not Applicable |
| File size | 3,078 |
| Date (UTC) | 21-Oct-2011 |
| Time (UTC) | 19:47 |
| File name | X86_c47763fe43b596d90c7c2775ee0dd650_31bf3856ad364e35_6.0.6002.22730_none_8251eeda0bf7e32b.manifest |
| File version | Not Applicable |
| File size | 692 |
| Date (UTC) | 21-Oct-2011 |
| Time (UTC) | 19:47 |
| File name | X86_ff124962614b4aa88f3c4a799f67e90d_31bf3856ad364e35_6.0.6002.22730_none_1dc1c2856de67291.manifest |
| File version | Not Applicable |
| File size | 696 |
| Date (UTC) | 21-Oct-2011 |
| Time (UTC) | 19:47 |
| File name | X86_microsoft-windows-http-api_31bf3856ad364e35_6.0.6002.22730_none_f7fbed04b3a808f3.manifest |
| File version | Not Applicable |
| File size | 4,708 |
| Date (UTC) | 21-Oct-2011 |
| Time (UTC) | 17:19 |
| File name | X86_microsoft-windows-http_31bf3856ad364e35_6.0.6002.22730_none_af10ac4e2f371c38.manifest |
| File version | Not Applicable |
| File size | 144,703 |
| Date (UTC) | 21-Oct-2011 |
| Time (UTC) | 17:22 |
Additional files for all supported x64-based versions of Windows Vista and of Windows Server 2008
| File name | Amd64_0e9954aa710303e9af470f9a20c3059c_31bf3856ad364e35_6.0.6002.22730_none_21fab38a641ad3a4.manifest |
|---|---|
| File version | Not Applicable |
| File size | 696 |
| Date (UTC) | 21-Oct-2011 |
| Time (UTC) | 19:47 |
| File name | Amd64_8a8744d23e5e10508bc31b129adf52c8_31bf3856ad364e35_6.0.6002.22730_none_eb078c334feb142f.manifest |
| File version | Not Applicable |
| File size | 1,040 |
| Date (UTC) | 21-Oct-2011 |
| Time (UTC) | 19:47 |
| File name | Amd64_microsoft-windows-http-api_31bf3856ad364e35_6.0.6002.22730_none_541a88886c057a29.manifest |
| File version | Not Applicable |
| File size | 4,722 |
| Date (UTC) | 21-Oct-2011 |
| Time (UTC) | 16:24 |
| File name | Amd64_microsoft-windows-http_31bf3856ad364e35_6.0.6002.22730_none_0b2f47d1e7948d6e.manifest |
| File version | Not Applicable |
| File size | 144,967 |
| Date (UTC) | 21-Oct-2011 |
| Time (UTC) | 16:27 |
| File name | Update.mum |
| File version | Not Applicable |
| File size | 3,102 |
| Date (UTC) | 21-Oct-2011 |
| Time (UTC) | 19:47 |
| File name | X86_microsoft-windows-http-api_31bf3856ad364e35_6.0.6002.22730_none_f7fbed04b3a808f3.manifest |
| File version | Not Applicable |
| File size | 4,708 |
| Date (UTC) | 21-Oct-2011 |
| Time (UTC) | 17:19 |
Additional files for all supported IA-64-based versions of Windows Server 2008
| File name | Ia64_937486422ecc087ca477812bfb385618_31bf3856ad364e35_6.0.6002.22730_none_e0fbc49508dda0f2.manifest |
|---|---|
| File version | Not Applicable |
| File size | 1,038 |
| Date (UTC) | 21-Oct-2011 |
| Time (UTC) | 19:47 |
| File name | Ia64_eb83b60347c51700d8462c02cebfe561_31bf3856ad364e35_6.0.6002.22730_none_69056b4620ca06a1.manifest |
| File version | Not Applicable |
| File size | 694 |
| Date (UTC) | 21-Oct-2011 |
| Time (UTC) | 19:47 |
| File name | Ia64_microsoft-windows-http-api_31bf3856ad364e35_6.0.6002.22730_none_f7fd90fab3a611ef.manifest |
| File version | Not Applicable |
| File size | 4,715 |
| Date (UTC) | 21-Oct-2011 |
| Time (UTC) | 16:24 |
| File name | Ia64_microsoft-windows-http_31bf3856ad364e35_6.0.6002.22730_none_af1250442f352534.manifest |
| File version | Not Applicable |
| File size | 144,957 |
| Date (UTC) | 21-Oct-2011 |
| Time (UTC) | 16:25 |
| File name | Update.mum |
| File version | Not Applicable |
| File size | 2,257 |
| Date (UTC) | 21-Oct-2011 |
| Time (UTC) | 19:47 |
| File name | X86_microsoft-windows-http-api_31bf3856ad364e35_6.0.6002.22730_none_f7fbed04b3a808f3.manifest |
| File version | Not Applicable |
| File size | 4,708 |
| Date (UTC) | 21-Oct-2011 |
| Time (UTC) | 17:19 |
Additional file information for Windows 7 and for Windows Server 2008 R2
Additional files for all supported x86-based versions of Windows 7
| File name | Update.mum |
|---|---|
| File version | Not Applicable |
| File size | 1,643 |
| Date (UTC) | 24-Nov-2011 |
| Time (UTC) | 20:02 |
| Platform | Not Applicable |
| File name | X86_4ceec32f5d8414531ede36ac95044832_31bf3856ad364e35_6.1.7601.21866_none_2cc2f90bda288c6f.manifest |
| File version | Not Applicable |
| File size | 692 |
| Date (UTC) | 24-Nov-2011 |
| Time (UTC) | 20:02 |
| Platform | Not Applicable |
| File name | X86_microsoft-windows-http_31bf3856ad364e35_6.1.7601.21866_none_af1df7c390615e9e.manifest |
| File version | Not Applicable |
| File size | 175,661 |
| Date (UTC) | 24-Nov-2011 |
| Time (UTC) | 07:20 |
| Platform | Not Applicable |
Additional files for all supported x64-based versions of Windows 7 and of Windows Server 2008 R2
| File name | Amd64_eb485ff954d31e1eb9389feab3b6cb3d_31bf3856ad364e35_6.1.7601.21866_none_3b57c8a52d3ae06c.manifest |
|---|---|
| File version | Not Applicable |
| File size | 696 |
| Date (UTC) | 24-Nov-2011 |
| Time (UTC) | 20:02 |
| Platform | Not Applicable |
| File name | Amd64_microsoft-windows-http_31bf3856ad364e35_6.1.7601.21866_none_0b3c934748becfd4.manifest |
| File version | Not Applicable |
| File size | 175,667 |
| Date (UTC) | 24-Nov-2011 |
| Time (UTC) | 08:08 |
| Platform | Not Applicable |
| File name | Update.mum |
| File version | Not Applicable |
| File size | 1,853 |
| Date (UTC) | 24-Nov-2011 |
| Time (UTC) | 20:02 |
| Platform | Not Applicable |
Additional files for all supported IA-64-based versions of Windows Server 2008 R2
| File name | Ia64_37b5b558ad5281f555e3c3726aa4cd3b_31bf3856ad364e35_6.1.7601.21866_none_c22af9b48ee5dfdb.manifest |
|---|---|
| File version | Not Applicable |
| File size | 694 |
| Date (UTC) | 24-Nov-2011 |
| Time (UTC) | 20:02 |
| Platform | Not Applicable |
| File name | Ia64_microsoft-windows-http_31bf3856ad364e35_6.1.7601.21866_none_af1f9bb9905f679a.manifest |
| File version | Not Applicable |
| File size | 175,664 |
| Date (UTC) | 24-Nov-2011 |
| Time (UTC) | 07:38 |
| Platform | Not Applicable |
| File name | Update.mum |
| File version | Not Applicable |
| File size | 1,447 |
| Date (UTC) | 24-Nov-2011 |
| Time (UTC) | 20:02 |
| Platform | Not Applicable |