This compatibility update is a software update that improves the compatibility experience in Windows RT 8.1, Windows 8.1, and Windows Server 2012 R2. Microsoft regularly releases Windows compatibility updates to improve the overall user experience. This compatibility update is dated April 2015.For more information about the improvements, see the "Applications or devices that experience a change in behavior after you install this update" section and the "Applications and devices that are included in this update" section.

How to obtain this update

Important Do not install a language pack after you install this update. If you do, the language-specific changes in the update will not be applied, and you will have to reinstall the update. For more information, see Add language packs to Windows.

Method 1: Windows Update

This update is available from Windows Update.

Method 2: Microsoft Download Center

The following files are available for download from the Microsoft Download Center:

Operating system

Update

All supported x86-based versions of Windows 8.1

Download Download the update package now.

All supported x64-based versions of Windows 8.1

Download Download the update package now.

All supported x64-based versions of Windows Server 2012 R2

Download Download the update package now.

Note The update for Windows RT 8.1 can be obtained only from Windows Update. For more information about how to download Microsoft support files, click the following article number to view the article in the Microsoft Knowledge Base:

119591 How to obtain Microsoft support files from online services Microsoft scanned this file for viruses. Microsoft used the most current virus-detection software that was available on the date that the file was posted. The file is stored on security-enhanced servers that help prevent any unauthorized changes to the file.

Update information

The kinds of problems that are resolved by application compatibility updates

When you try to install and run certain games or applications in Windows RT 8.1, Windows 8.1, or Windows Server 2012 R2, you may experience one or more of the following symptoms:

  • The game, the application, or the driver is installed incorrectly.

  • The game, the application, or the driver causes system instability.

  • The primary functions of the game, the application, or the firmware do not work correctly.

Applications or devices that experience a change in behavior after you install this update

The following table lists the applications and devices that were included in this cumulative update package. This table also describes the behavior of these applications and devices after you install the update.Compatibility updates trigger several changes in Windows RT 8.1, Windows 8.1, and Windows Server 2012 R2. The following are the most common:

Hard block

This prevents an application that is incompatible with Windows RT 8.1, Windows 8.1, or Windows Server 2012 R2 from running on the system.Note Microsoft enables Windows to put a hard block on a non-Microsoft application only if the manufacturer is notified.

Soft block

This notifies you when a primary function of the application may not work or may cause application instability.

Driver block

This may block an existing driver on your computer. When the driver is migrated during the upgrade, an Inbox driver will be installed.

Applications and devices that are included in this update

Applications or Devices

Version

Behavior after you install the update

Microchip HUB

not available

Storage devices that are connected to the Microchip hub works correctly after safe removal.

PSC (Datalogic) Scanner

not available

Embedded scanner under xHCI controller works correctly.

AMD USB xHCI Controller

not available

Eliminate the AV_USBXHCI!Bulk_Transfer_CompleteCancelable crash.

AsMedia USB xHCI Controller

not available

Eliminate the AV_USBXHCI!Bulk_Transfer_CompleteCancelable crash.

ETron USB xHCI Controller

not available

Eliminate the AV_USBXHCI!Bulk_Transfer_CompleteCancelable crash.

Intel Pantherpoint xHCI Controller

not available

Eliminate the AV_USBXHCI!Bulk_Transfer_CompleteCancelable crash.

Intel Lynxpoint xHCI Controller

not available

Eliminate the AV_USBXHCI!Bulk_Transfer_CompleteCancelable crash.

NEC Renesas xHCI Controller

not available

Eliminate the AV_USBXHCI!Bulk_Transfer_CompleteCancelable crash.

NVidia xHCI Controller

not available

Eliminate the AV_USBXHCI!Bulk_Transfer_CompleteCancelable crash.

VIA xHCI Controller

not available

Eliminate the AV_USBXHCI!Bulk_Transfer_CompleteCancelable crash.

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

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 RT 8.1, Windows 8.1 and Windows Server 2012 R2" 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 Windows RT 8.1

File name

File version

File size

Date

Time

Platform

Apphelp.dll

6.3.9600.17725

397,312

11-Mar-2015

00:44

Not applicable

Sdbinst.exe

6.3.9600.17725

20,992

11-Mar-2015

00:38

Not applicable

Shimeng.dll

6.3.9600.17031

6,144

22-Feb-2014

09:59

Not applicable

Acres.dll

6.3.9600.16384

310,784

22-Aug-2013

03:16

Not applicable

Sysmain.sdb

Not applicable

39,336

10-Mar-2015

22:17

Not applicable

Msimain.sdb

Not applicable

286

10-Mar-2015

22:17

Not applicable

Acgenral.dll

6.3.9600.17725

9,728

11-Mar-2015

00:44

Not applicable

Acwinrt.dll

6.3.9600.16384

8,704

22-Aug-2013

02:15

Not applicable

Acspecfc.dll

6.3.9600.17725

9,728

11-Mar-2015

00:26

Not applicable

Drvmain.sdb

Not applicable

61,802

10-Mar-2015

22:17

Not applicable

For all supported x86-based versions of Windows 8.1

File name

File version

File size

Date

Time

Platform

Apphelp.dll

6.3.9600.17415

642,560

29-Oct-2014

02:00

x86

Sdbinst.exe

6.3.9600.17725

21,504

11-Mar-2015

01:09

x86

Shimeng.dll

6.3.9600.17415

5,632

29-Oct-2014

02:00

x86

Acres.dll

6.3.9600.16384

310,784

22-Aug-2013

04:16

x86

Sysmain.sdb

Not applicable

3,833,752

10-Mar-2015

22:18

Not applicable

Msimain.sdb

Not applicable

2,726,550

10-Mar-2015

22:18

Not applicable

Acgenral.dll

6.3.9600.17725

2,490,368

11-Mar-2015

00:32

x86

Acwinrt.dll

6.3.9600.17415

8,704

29-Oct-2014

01:01

x86

Acspecfc.dll

6.3.9600.17725

449,024

11-Mar-2015

00:35

x86

Drvmain.sdb

Not applicable

121,202

10-Mar-2015

22:18

Not applicable

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

Apphelp.dll

6.3.9600.17415

564,224

29-Oct-2014

02:44

x64

Sdbinst.exe

6.3.9600.17725

24,576

11-Mar-2015

01:49

x64

Shimeng.dll

6.3.9600.17415

7,168

29-Oct-2014

02:45

x64

Sysmain.sdb

Not applicable

433,488

10-Mar-2015

22:17

Not applicable

Msimain.sdb

Not applicable

2,756,926

10-Mar-2015

22:17

Not applicable

Acgenral.dll

6.3.9600.17725

317,440

11-Mar-2015

00:58

x64

Acwinrt.dll

6.3.9600.17415

10,752

29-Oct-2014

01:21

x64

Acspecfc.dll

6.3.9600.17725

42,496

11-Mar-2015

01:05

x64

Drvmain.sdb

Not applicable

122,480

10-Mar-2015

22:17

Not applicable

Apphelp.dll

6.3.9600.17415

642,560

29-Oct-2014

02:00

x86

Sdbinst.exe

6.3.9600.17725

21,504

11-Mar-2015

01:09

x86

Shimeng.dll

6.3.9600.17415

5,632

29-Oct-2014

02:00

x86

Acres.dll

6.3.9600.16384

310,784

22-Aug-2013

04:16

x86

Sysmain.sdb

Not applicable

3,833,752

10-Mar-2015

22:18

Not applicable

Acgenral.dll

6.3.9600.17725

2,490,368

11-Mar-2015

00:32

x86

Acwinrt.dll

6.3.9600.17415

8,704

29-Oct-2014

01:01

x86

Acspecfc.dll

6.3.9600.17725

449,024

11-Mar-2015

00:35

x86

Additional file information

Additional file information for Windows RT 8.1, Windows 8.1 and Windows Server 2012 R2

Additional file information for Windows RT 8.1

File property

Value

File name

Arm_075f0050ff4eef271442cf7c6aa1ffc0_31bf3856ad364e35_6.3.9600.17725_none_90b187c919c8ec95.manifest

File version

Not applicable

File size

725

Date (UTC)

12-Mar-2015

Time (UTC)

23:40

File name

Arm_444de47e4864e9ff6dfcb7c01719d383_31bf3856ad364e35_6.3.9600.17725_none_27b6ea069170406f.manifest

File version

Not applicable

File size

725

Date (UTC)

12-Mar-2015

Time (UTC)

23:40

File name

Arm_4b0b01c21c35f3fc140bab5dce2bfbfc_31bf3856ad364e35_6.3.9600.17725_none_6a328c41b625c7fd.manifest

File version

Not applicable

File size

725

Date (UTC)

12-Mar-2015

Time (UTC)

23:40

File name

Arm_5554d51651f627cf10242dc31bc084d3_31bf3856ad364e35_6.3.9600.17725_none_32adb6a4f9dbf6b6.manifest

File version

Not applicable

File size

725

Date (UTC)

12-Mar-2015

Time (UTC)

23:40

File name

Arm_9e46cf8b474a94e84685ce2f7e44c3e6_31bf3856ad364e35_6.3.9600.17725_none_45666579be6c4694.manifest

File version

Not applicable

File size

725

Date (UTC)

12-Mar-2015

Time (UTC)

23:40

File name

Arm_cd8efd051f6128889462b9254cf4554b_31bf3856ad364e35_6.3.9600.17725_none_5eed5fd4f5934bac.manifest

File version

Not applicable

File size

725

Date (UTC)

12-Mar-2015

Time (UTC)

23:40

File name

Arm_microsoft-windows-a..ence-infrastructure_31bf3856ad364e35_6.3.9600.17725_none_69f50b3f681f0ab5.manifest

File version

Not applicable

File size

13,037

Date (UTC)

12-Mar-2015

Time (UTC)

23:40

File name

Arm_microsoft-windows-a..ence-mitigations-c1_31bf3856ad364e35_6.3.9600.17725_none_a1063fab0db19fbf.manifest

File version

Not applicable

File size

3,312

Date (UTC)

12-Mar-2015

Time (UTC)

23:40

File name

Arm_microsoft-windows-a..ence-mitigations-c2_31bf3856ad364e35_6.3.9600.17725_none_a1073ff50db0b916.manifest

File version

Not applicable

File size

2,558

Date (UTC)

11-Mar-2015

Time (UTC)

01:24

File name

Arm_microsoft-windows-a..ence-mitigations-c3_31bf3856ad364e35_6.3.9600.17725_none_a108403f0dafd26d.manifest

File version

Not applicable

File size

3,310

Date (UTC)

12-Mar-2015

Time (UTC)

23:40

File name

Arm_microsoft-windows-a..ence-mitigations-c4_31bf3856ad364e35_6.3.9600.17725_none_a10940890daeebc4.manifest

File version

Not applicable

File size

2,552

Date (UTC)

11-Mar-2015

Time (UTC)

01:24

File name

Arm_microsoft-windows-a..ence-mitigations-c7_31bf3856ad364e35_6.3.9600.17725_none_a10c41670dac37c9.manifest

File version

Not applicable

File size

1,867

Date (UTC)

11-Mar-2015

Time (UTC)

01:24

Additional files for all supported x86-based versions of Windows 8.1

File property

Value

File name

X86_18c90c8f3dd3d66330a0bc91320e680a_31bf3856ad364e35_6.3.9600.17725_none_9c10f79f0e99b33e.manifest

File version

Not applicable

File size

725

Date (UTC)

12-Mar-2015

Time (UTC)

23:40

File name

X86_32030cfda08755983c00cb8cd607296f_31bf3856ad364e35_6.3.9600.17725_none_92371020f931bb8f.manifest

File version

Not applicable

File size

725

Date (UTC)

12-Mar-2015

Time (UTC)

23:40

File name

X86_77084f1ba8ebb2650a5f6ca9fe9c7a26_31bf3856ad364e35_6.3.9600.17725_none_c28d11eae9b381a5.manifest

File version

Not applicable

File size

725

Date (UTC)

12-Mar-2015

Time (UTC)

23:40

File name

X86_8b1f7122a604e3010f46a250e038f203_31bf3856ad364e35_6.3.9600.17725_none_2437ebe5d1bf23fb.manifest

File version

Not applicable

File size

725

Date (UTC)

12-Mar-2015

Time (UTC)

23:40

File name

X86_be7a1b519ae4479fcb8b4d18e4292065_31bf3856ad364e35_6.3.9600.17725_none_103707cee25b536d.manifest

File version

Not applicable

File size

725

Date (UTC)

12-Mar-2015

Time (UTC)

23:40

File name

X86_cebf874e74b69a40d1e2fb81afd33dc6_31bf3856ad364e35_6.3.9600.17725_none_f7d0405d2d0c4897.manifest

File version

Not applicable

File size

725

Date (UTC)

12-Mar-2015

Time (UTC)

23:40

File name

X86_microsoft-windows-a..ence-infrastructure_31bf3856ad364e35_6.3.9600.17725_none_69f298e76821ebef.manifest

File version

Not applicable

File size

13,037

Date (UTC)

12-Mar-2015

Time (UTC)

23:43

File name

X86_microsoft-windows-a..ence-mitigations-c1_31bf3856ad364e35_6.3.9600.17725_none_a103cd530db480f9.manifest

File version

Not applicable

File size

3,312

Date (UTC)

12-Mar-2015

Time (UTC)

23:44

File name

X86_microsoft-windows-a..ence-mitigations-c2_31bf3856ad364e35_6.3.9600.17725_none_a104cd9d0db39a50.manifest

File version

Not applicable

File size

2,558

Date (UTC)

11-Mar-2015

Time (UTC)

02:20

File name

X86_microsoft-windows-a..ence-mitigations-c3_31bf3856ad364e35_6.3.9600.17725_none_a105cde70db2b3a7.manifest

File version

Not applicable

File size

3,310

Date (UTC)

12-Mar-2015

Time (UTC)

23:44

File name

X86_microsoft-windows-a..ence-mitigations-c4_31bf3856ad364e35_6.3.9600.17725_none_a106ce310db1ccfe.manifest

File version

Not applicable

File size

2,552

Date (UTC)

11-Mar-2015

Time (UTC)

02:20

File name

X86_microsoft-windows-a..ence-mitigations-c7_31bf3856ad364e35_6.3.9600.17725_none_a109cf0f0daf1903.manifest

File version

Not applicable

File size

1,867

Date (UTC)

11-Mar-2015

Time (UTC)

02:20

Additional files for all supported x64-based versions of Windows 8.1 and of Windows Server 2012 R2

File property

Value

File name

Amd64_4103e87fd4391c31b49b0e0f3476e08c_31bf3856ad364e35_6.3.9600.17725_none_ee1af89fce415d87.manifest

File version

Not applicable

File size

729

Date (UTC)

12-Mar-2015

Time (UTC)

23:40

File name

Amd64_5b6ed6835dad9e505203dff7de1cb586_31bf3856ad364e35_6.3.9600.17725_none_2d715b5c2b11344c.manifest

File version

Not applicable

File size

729

Date (UTC)

12-Mar-2015

Time (UTC)

23:40

File name

Amd64_8465f6bfe4bf959df27ede45eed3c19d_31bf3856ad364e35_6.3.9600.17725_none_473773ffdb841644.manifest

File version

Not applicable

File size

729

Date (UTC)

12-Mar-2015

Time (UTC)

23:40

File name

Amd64_8963f0d31fbfc46b61aae627fa55ab6f_31bf3856ad364e35_6.3.9600.17725_none_03f20dec9ac675ad.manifest

File version

Not applicable

File size

729

Date (UTC)

12-Mar-2015

Time (UTC)

23:40

File name

Amd64_a3a2bffc1cb21ba62a2bd2f347e34d96_31bf3856ad364e35_6.3.9600.17725_none_b2133d04159bfdaf.manifest

File version

Not applicable

File size

729

Date (UTC)

12-Mar-2015

Time (UTC)

23:40

File name

Amd64_a784a6dbcf76353856b83a401259204f_31bf3856ad364e35_6.3.9600.17725_none_456d2d238fe8c061.manifest

File version

Not applicable

File size

729

Date (UTC)

12-Mar-2015

Time (UTC)

23:40

File name

Amd64_af271926db28c514b9ba27463eb7acfc_31bf3856ad364e35_6.3.9600.17725_none_ee4b6b7f6f8a0159.manifest

File version

Not applicable

File size

729

Date (UTC)

12-Mar-2015

Time (UTC)

23:40

File name

Amd64_be7a1b519ae4479fcb8b4d18e4292065_31bf3856ad364e35_6.3.9600.17725_none_6c55a3529ab8c4a3.manifest

File version

Not applicable

File size

727

Date (UTC)

12-Mar-2015

Time (UTC)

23:40

File name

Amd64_c3cbeef4aa9f04038db037dac8cccfa6_31bf3856ad364e35_6.3.9600.17725_none_aba08315e83d5810.manifest

File version

Not applicable

File size

729

Date (UTC)

12-Mar-2015

Time (UTC)

23:40

File name

Amd64_cebf874e74b69a40d1e2fb81afd33dc6_31bf3856ad364e35_6.3.9600.17725_none_53eedbe0e569b9cd.manifest

File version

Not applicable

File size

727

Date (UTC)

12-Mar-2015

Time (UTC)

23:40

File name

Amd64_e6f61db667adabb71a2fc7951bb9714a_31bf3856ad364e35_6.3.9600.17725_none_fd8f12d16f83f888.manifest

File version

Not applicable

File size

729

Date (UTC)

12-Mar-2015

Time (UTC)

23:40

File name

Amd64_f66e18e6dc3659a155286ce84c76e86e_31bf3856ad364e35_6.3.9600.17725_none_a177bc909b5dea9e.manifest

File version

Not applicable

File size

729

Date (UTC)

12-Mar-2015

Time (UTC)

23:40

File name

Amd64_microsoft-windows-a..ence-infrastructure_31bf3856ad364e35_6.3.9600.17725_none_c611346b207f5d25.manifest

File version

Not applicable

File size

13,368

Date (UTC)

12-Mar-2015

Time (UTC)

23:48

File name

Amd64_microsoft-windows-a..ence-mitigations-c1_31bf3856ad364e35_6.3.9600.17725_none_fd2268d6c611f22f.manifest

File version

Not applicable

File size

2,573

Date (UTC)

11-Mar-2015

Time (UTC)

03:03

File name

Amd64_microsoft-windows-a..ence-mitigations-c2_31bf3856ad364e35_6.3.9600.17725_none_fd236920c6110b86.manifest

File version

Not applicable

File size

2,562

Date (UTC)

11-Mar-2015

Time (UTC)

03:03

File name

Amd64_microsoft-windows-a..ence-mitigations-c3_31bf3856ad364e35_6.3.9600.17725_none_fd24696ac61024dd.manifest

File version

Not applicable

File size

3,336

Date (UTC)

12-Mar-2015

Time (UTC)

23:48

File name

Amd64_microsoft-windows-a..ence-mitigations-c4_31bf3856ad364e35_6.3.9600.17725_none_fd2569b4c60f3e34.manifest

File version

Not applicable

File size

2,567

Date (UTC)

11-Mar-2015

Time (UTC)

03:03

File name

Amd64_microsoft-windows-a..ence-mitigations-c7_31bf3856ad364e35_6.3.9600.17725_none_fd286a92c60c8a39.manifest

File version

Not applicable

File size

1,869

Date (UTC)

11-Mar-2015

Time (UTC)

03:03

File name

Wow64_microsoft-windows-a..ence-infrastructure_31bf3856ad364e35_6.3.9600.17725_none_d065debd54e01f20.manifest

File version

Not applicable

File size

13,039

Date (UTC)

12-Mar-2015

Time (UTC)

23:48

File name

Wow64_microsoft-windows-a..ence-mitigations-c1_31bf3856ad364e35_6.3.9600.17725_none_07771328fa72b42a.manifest

File version

Not applicable

File size

3,314

Date (UTC)

12-Mar-2015

Time (UTC)

23:48

File name

Wow64_microsoft-windows-a..ence-mitigations-c2_31bf3856ad364e35_6.3.9600.17725_none_07781372fa71cd81.manifest

File version

Not applicable

File size

1,141

Date (UTC)

11-Mar-2015

Time (UTC)

02:18

File name

Wow64_microsoft-windows-a..ence-mitigations-c7_31bf3856ad364e35_6.3.9600.17725_none_077d14e4fa6d4c34.manifest

File version

Not applicable

File size

450

Date (UTC)

11-Mar-2015

Time (UTC)

02:18

File name

X86_microsoft-windows-a..ence-mitigations-c3_31bf3856ad364e35_6.3.9600.17725_none_a105cde70db2b3a7.manifest

File version

Not applicable

File size

3,310

Date (UTC)

12-Mar-2015

Time (UTC)

23:48

File name

X86_microsoft-windows-a..ence-mitigations-c4_31bf3856ad364e35_6.3.9600.17725_none_a106ce310db1ccfe.manifest

File version

Not applicable

File size

2,552

Date (UTC)

11-Mar-2015

Time (UTC)

02:20

References

See the terminology that Microsoft uses to describe software updates.

The third-party products that this article discusses are manufactured by companies that are independent of Microsoft. Microsoft makes no warranty, implied or otherwise, about the performance or reliability of these products.

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