Applies ToWindows 8.1 Enterprise Windows 8.1 Windows 8.1 Pro Windows RT 8.1 Windows Server 2012 R2 Datacenter Windows Server 2012 R2 Foundation Windows Server 2012 R2 Standard Windows Server 2012 R2 Essentials

Summary

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 May 2014.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.

More Information

Update information

How to obtain this update

This compatibility update is offered when you upgrade to the release version of Windows RT 8.1, Windows 8.1, or Windows Server 2012 R2.

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 works incorrectly.

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

Marcrium Reflect

Up to 5.0.*

Blocks upgrade if the application is installed to prevent data loss.

Windows Mobile Device Center

6.1.*

Informs the user to reinstall this application after upgrade.

Kaspersky Endpoint Security

Up to 10.2.*

Blocks upgrade if the application is installed to prevent data loss.

Vmware Player

10.*

Informs the user to reinstall this application after upgrade.

Avira Antivirus

2014

Informs the user to reinstall this application after upgrade.

MG25-Terran2+G USB 3.0 HDD

not available

Improves user experience.

The global version of this update 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.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, 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 Windows RT 8.1

File name

File version

File size

Date

Time

Platform

Acres.dll

6.3.9600.16384

310,784

21-Aug-2013

12:16

Not applicable

Sysmain.sdb

Not applicable

39,336

17-Apr-2014

11:39

Not applicable

Msimain.sdb

Not applicable

286

17-Apr-2014

11:39

Not applicable

Acgenral.dll

6.3.9600.16459

9,728

08-Nov-2013

15:31

Not applicable

Acwinrt.dll

6.3.9600.16384

8,704

21-Aug-2013

11:15

Not applicable

Acspecfc.dll

6.3.9600.16427

9,728

12-Oct-2013

06:13

Not applicable

Drvmain.sdb

Not applicable

58,894

17-Apr-2014

11:39

Not applicable

For all supported x86-based versions of Windows 8.1

File name

File version

File size

Date

Time

Platform

Acres.dll

6.3.9600.16384

310,784

21-Aug-2013

13:16

x86

Sysmain.sdb

Not applicable

3,835,136

17-Apr-2014

11:47

Not applicable

Msimain.sdb

Not applicable

2,727,022

17-Apr-2014

11:47

Not applicable

Acgenral.dll

6.3.9600.17098

2,441,216

17-Apr-2014

18:14

x86

Acwinrt.dll

6.3.9600.16384

8,704

21-Aug-2013

11:47

x86

Acspecfc.dll

6.3.9600.17050

442,880

12-Mar-2014

15:08

x86

Drvmain.sdb

Not applicable

118,472

17-Apr-2014

11:47

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

Sysmain.sdb

Not applicable

433,638

17-Apr-2014

11:43

Not applicable

Msimain.sdb

Not applicable

2,757,398

17-Apr-2014

11:43

Not applicable

Acgenral.dll

6.3.9600.17021

305,664

09-Feb-2014

08:17

x64

Acwinrt.dll

6.3.9600.16384

10,240

21-Aug-2013

18:54

x64

Acspecfc.dll

6.3.9600.16427

41,472

12-Oct-2013

07:24

x64

Drvmain.sdb

Not applicable

119,762

17-Apr-2014

11:43

Not applicable

Acres.dll

6.3.9600.16384

310,784

21-Aug-2013

13:16

x86

Sysmain.sdb

Not applicable

3,835,136

17-Apr-2014

11:47

Not applicable

Acgenral.dll

6.3.9600.17098

2,441,216

17-Apr-2014

18:14

x86

Acwinrt.dll

6.3.9600.16384

8,704

21-Aug-2013

11:47

x86

Acspecfc.dll

6.3.9600.17050

442,880

12-Mar-2014

15:08

x86

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

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