This article describes a hotfix that improves the performance of WinHTTP in Windows RT 8.1, Windows 8.1, and Windows Server 2012 R2. Before you apply this hotfix, notice that this hotfix has a prerequisite.
About this hotfix
This hotfix fixes a rare deadlock between WinHTTP and LSASS. This deadlock happens when WinHTTP handles lots of concurrent requests and consumes all the system threads.
Hotfix information
Important Do not install a language pack after you install this hotfix. If you do, the language-specific changes in the hotfix will not be applied, and you will have to reinstall the hotfix. For more information, see Add language packs to Windows.
A supported hotfix is available from Microsoft. However, this hotfix is intended to correct only the problem that is described in this article. Apply this hotfix only to systems that are experiencing this specific problem.
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, submit a request to 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 have April 2014 update rollup for Windows RT 8.1, Windows 8.1, and Windows Server 2012 R2 (2919355) installed in Windows 8.1 or Windows Server 2012 R2.
Registry information
To use the hotfix in this package, you do not have to make any changes to the registry.
Restart requirement
You may have to 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 8.1 and Windows Server 2012 R2 file information and notes
Important Windows 8.1 hotfixes and Windows Server 2012 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 8.1/Windows Server 2012 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, milestone (RTM, SPn), and service branch (LDR, GDR) can be identified by examining the file version numbers as shown in the following table:
Version Product Milestone Service branch 6.3.960 0.17xxx Windows 8.1 and Windows Server 2012 R2 RTM GDR The MANIFEST files (.manifest) and the MUM files (.mum) that are installed for each environment are listed separately in the "Additional file information" section. MUM, MANIFEST, and the associated security catalog (.cat) files, are very 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 8.1
| File name | File version | File size | Date | Time | Platform |
|---|---|---|---|---|---|
| Webio.dll | 6.3.9600.17715 | 413,696 | 27-Feb-2015 | 01:31 | x86 |
For all supported x64-based versions of Windows 8.1 and of Windows Server 2012 R2
| File name | File version | File size | Date | Time | Platform |
|---|---|---|---|---|---|
| Webio.dll | 6.3.9600.17715 | 510,976 | 27-Feb-2015 | 01:51 | x64 |
| Webio.dll | 6.3.9600.17715 | 413,696 | 27-Feb-2015 | 01:31 | x86 |
For all supported Windows RT 8.1
| File name | File version | File size | Date | Time | Platform |
|---|---|---|---|---|---|
| Webio.dll | 6.3.9600.17715 | 356,864 | 27-Feb-2015 | 01:13 | Not applicable |
Additional file information
Additional file information for Windows 8.1 and for Windows Server 2012 R2
Additional files for all supported x86-based versions of Windows 8.1
| File property | Value |
|---|---|
| File name | X86_4d1a3e1d3e6fab893eb9ab5b99aa48ca_31bf3856ad364e35_6.3.9600.17715_none_ccc8ab0b7041af5a.manifest |
| File version | Not applicable |
| File size | 693 |
| Date (UTC) | 27-Feb-2015 |
| Time (UTC) | 19:40 |
| Platform | Not applicable |
| File name | X86_microsoft-windows-webio_31bf3856ad364e35_6.3.9600.17715_none_f1d69f32fa1333b7.manifest |
| File version | Not applicable |
| File size | 2,523 |
| Date (UTC) | 27-Feb-2015 |
| Time (UTC) | 04:51 |
| Platform | Not applicable |
Additional files for all supported x64-based versions of Windows 8.1 and of Windows Server 2012 R2
| File property | Value |
|---|---|
| File name | Amd64_aaeb7133afec74d2d115d673c4bfcc55_31bf3856ad364e35_6.3.9600.17715_none_aba61caf5517e289.manifest |
| File version | Not applicable |
| File size | 697 |
| Date (UTC) | 27-Feb-2015 |
| Time (UTC) | 19:40 |
| Platform | Not applicable |
| File name | Amd64_b039143f4573bc76342acaeb338ec706_31bf3856ad364e35_6.3.9600.17715_none_2b0a32f3ca52bcc9.manifest |
| File version | Not applicable |
| File size | 697 |
| Date (UTC) | 27-Feb-2015 |
| Time (UTC) | 19:40 |
| Platform | Not applicable |
| File name | Amd64_microsoft-windows-webio_31bf3856ad364e35_6.3.9600.17715_none_4df53ab6b270a4ed.manifest |
| File version | Not applicable |
| File size | 2,527 |
| Date (UTC) | 27-Feb-2015 |
| Time (UTC) | 05:11 |
| Platform | Not applicable |
| File name | Wow64_microsoft-windows-webio_31bf3856ad364e35_6.3.9600.17715_none_5849e508e6d166e8.manifest |
| File version | Not applicable |
| File size | 2,525 |
| Date (UTC) | 27-Feb-2015 |
| Time (UTC) | 04:51 |
| Platform | Not applicable |
Additional files for all supported Windows RT 8.1
| File property | Value |
|---|---|
| File name | Arm_1e69594a6c123590373fa036982099f4_31bf3856ad364e35_6.3.9600.17715_none_aea16253a6ffb155.manifest |
| File version | Not applicable |
| File size | 693 |
| Date (UTC) | 27-Feb-2015 |
| Time (UTC) | 19:40 |
| Platform | Not applicable |
| File name | Arm_microsoft-windows-webio_31bf3856ad364e35_6.3.9600.17715_none_f1d9118afa10527d.manifest |
| File version | Not applicable |
| File size | 2,523 |
| Date (UTC) | 27-Feb-2015 |
| Time (UTC) | 04:53 |
| Platform | Not applicable |
Status
Microsoft has confirmed that this is a problem in the Microsoft products that are listed in the "Applies to" section.
References
See the terminology that Microsoft uses to describe software updates.