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Applies to:

Microsoft .NET Framework 3.5.1

This update for Windows 7 Service Pack 1 (SP1) and Server 2008 R2 Service Pack 1 (SP1) includes cumulative reliability improvements in .NET Framework 3.5.1. We recommend that you apply this update as part of your regular maintenance routines. Before you install this update, see the Prerequisites and Restart requirement sections.

Important

  • If you install a language pack after you install this update, you must reinstall this update. Therefore, we recommend that you install any language packs that you need before you install this update. For more information, see Add language packs to Windows.

Quality and reliability improvements

CLR1

  • Addressed an issue where the Framework would throw an exception is the year in the parsed date is greater or equal the year start the next era. Now, the framework will not throw such exception.

  • Updated Japanese Era dates that are formatted for the first year in an era and for which the format pattern uses “y年”. The format of the year together with the symbol “元” is supported instead of using year number 1. Also, formatting day numbers that include “元” is supported.

  • Removed dependency of single quote to output the Gannen character in Japanese Era formatting.

  • Addressed registry key setting HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Nls\Calendars\Japanese\Eras to support Japanese Era.

1 Common Language Runtime (CLR)

Additional information about this update

For more information about this update as it relates to Windows 7 SP1 and Windows Server 2008 R2 SP1, see the following article in the Microsoft Knowledge Base:

4489486 March 2019 Update for .NET Framework 3.5.1, 4.5.2, 4.6, 4.6.1, 4.6.2, 4.7, 4.7.1, and 4.7.2 for Windows 7 SP1 and Server 2008 R2 SP1 (KB 4489486)

Known Issues

Microsoft is not currently aware of any issues with this update.

How to obtain and install the update

Microsoft Update Catalog

To get the standalone package for this update, go to the Microsoft Update Catalog.

Windows Software Update Services (WSUS)

On your WSUS server, follow these steps:

  1. Select Start, select Administrative Tools, and then select Microsoft Windows Server Update Services 3.0.

  2. Expand ComputerName, and then select Action.

  3. Select Import Updates.

  4. WSUS opens a browser window in which you may be prompted to install an ActiveX control. You must install the ActiveX control to continue.

  5. After the ActiveX control is installed, you see the Microsoft Update Catalog screen. Type 4489486 in the Search box, and then select Search

  6. Locate the .NET Framework packages that match the operating systems, languages, and processors in your environment. Select Add to add them to your basket.

  7. After you select all the packages that you require, select View Basket.

  8. To import the packages to your WSUS server, select Import.

  9. After the packages are imported, select Close to return to WSUS.

The updates are now available for installation through WSUS.

Prerequisites

To apply this update, you must have .NET Framework 3.5.1 installed.

Restart requirement

You must restart the computer after you apply this update if any affected files are being used. We recommend that you exit all .NET Framework-based applications before you apply this update.

Update replacement information

This update does not replace a previously released update.

File information

The English (United States) version of this software 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.

Windows 7 and Windows Server 2008 R2

Note: The MANIFEST files (.manifest) and the MUM files (.mum) that are installed for each environment are listed 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.


Additional file information

ia64 Windows Server 2008 R2

File name

File version

File size

Date

Time

Platform

Big5.nlp

Not applicable

66,728

13-Nov-2018

19:28

Not applicable

Bopomofo.nlp

Not applicable

82,172

13-Nov-2018

19:28

Not applicable

Ksc.nlp

Not applicable

116,756

13-Nov-2018

19:28

Not applicable

Mscorlib.dll

2.0.50727.8805

4,018,176

05-Feb-2019

14:06

IA-64

Normidna.nlp

Not applicable

59,342

13-Nov-2018

19:29

Not applicable

Normnfc.nlp

Not applicable

45,794

13-Nov-2018

19:29

Not applicable

Normnfd.nlp

Not applicable

39,284

13-Nov-2018

19:29

Not applicable

Normnfkc.nlp

Not applicable

66,384

13-Nov-2018

19:29

Not applicable

Normnfkd.nlp

Not applicable

60,294

13-Nov-2018

19:29

Not applicable

Prc.nlp

Not applicable

83,748

13-Nov-2018

19:29

Not applicable

Prcp.nlp

Not applicable

83,748

13-Nov-2018

19:29

Not applicable

Sortkey.nlp

Not applicable

262,148

13-Nov-2018

19:29

Not applicable

Sorttbls.nlp

Not applicable

20,320

13-Nov-2018

19:29

Not applicable

Xjis.nlp

Not applicable

28,288

13-Nov-2018

19:29

Not applicable

Mscordacwks.dll

2.0.50727.8805

3,083,416

05-Feb-2019

14:06

IA-64

Mscorwks.dll

2.0.50727.8805

20,404,888

05-Feb-2019

14:06

IA-64

Sos.dll

2.0.50727.8805

873,624

05-Feb-2019

14:06

IA-64

Big5.nlp

Not applicable

66,728

13-Nov-2018

19:25

Not applicable

Bopomofo.nlp

Not applicable

82,172

13-Nov-2018

19:25

Not applicable

Ksc.nlp

Not applicable

116,756

13-Nov-2018

19:26

Not applicable

Mscorlib.dll

2.0.50727.8805

4,558,848

05-Feb-2019

14:06

x86

Normidna.nlp

Not applicable

59,342

13-Nov-2018

19:27

Not applicable

Normnfc.nlp

Not applicable

45,794

13-Nov-2018

19:27

Not applicable

Normnfd.nlp

Not applicable

39,284

13-Nov-2018

19:27

Not applicable

Normnfkc.nlp

Not applicable

66,384

13-Nov-2018

19:27

Not applicable

Normnfkd.nlp

Not applicable

60,294

13-Nov-2018

19:27

Not applicable

Prc.nlp

Not applicable

83,748

13-Nov-2018

19:27

Not applicable

Prcp.nlp

Not applicable

83,748

13-Nov-2018

19:27

Not applicable

Sortkey.nlp

Not applicable

262,148

13-Nov-2018

19:27

Not applicable

Sorttbls.nlp

Not applicable

20,320

13-Nov-2018

19:27

Not applicable

Xjis.nlp

Not applicable

28,288

13-Nov-2018

19:27

Not applicable

Mscordacwks.dll

2.0.50727.8805

990,360

05-Feb-2019

14:06

x86

Mscorwks.dll

2.0.50727.8805

5,947,032

05-Feb-2019

14:06

x86

Sos.dll

2.0.50727.8805

389,784

05-Feb-2019

14:06

x86

x64 Windows 7 and Windows Server 2008 R2

File name

File version

File size

Date

Time

Platform

Big5.nlp

Not applicable

66,728

13-Nov-2018

19:24

Not applicable

Bopomofo.nlp

Not applicable

82,172

13-Nov-2018

19:24

Not applicable

Ksc.nlp

Not applicable

116,756

13-Nov-2018

19:24

Not applicable

Mscorlib.dll

2.0.50727.8805

4,575,232

05-Feb-2019

14:06

x64

Normidna.nlp

Not applicable

59,342

13-Nov-2018

19:25

Not applicable

Normnfc.nlp

Not applicable

45,794

13-Nov-2018

19:25

Not applicable

Normnfd.nlp

Not applicable

39,284

13-Nov-2018

19:25

Not applicable

Normnfkc.nlp

Not applicable

66,384

13-Nov-2018

19:25

Not applicable

Normnfkd.nlp

Not applicable

60,294

13-Nov-2018

19:25

Not applicable

Prc.nlp

Not applicable

83,748

13-Nov-2018

19:25

Not applicable

Prcp.nlp

Not applicable

83,748

13-Nov-2018

19:25

Not applicable

Sortkey.nlp

Not applicable

262,148

13-Nov-2018

19:25

Not applicable

Sorttbls.nlp

Not applicable

20,320

13-Nov-2018

19:25

Not applicable

Xjis.nlp

Not applicable

28,288

13-Nov-2018

19:25

Not applicable

Mscordacwks.dll

2.0.50727.8805

1,757,336

05-Feb-2019

14:06

x64

Mscorwks.dll

2.0.50727.8805

10,007,192

05-Feb-2019

14:06

x64

Sos.dll

2.0.50727.8805

486,040

05-Feb-2019

14:06

x64

Big5.nlp

Not applicable

66,728

13-Nov-2018

19:25

Not applicable

Bopomofo.nlp

Not applicable

82,172

13-Nov-2018

19:25

Not applicable

Ksc.nlp

Not applicable

116,756

13-Nov-2018

19:26

Not applicable

Mscorlib.dll

2.0.50727.8805

4,558,848

05-Feb-2019

14:06

x86

Normidna.nlp

Not applicable

59,342

13-Nov-2018

19:27

Not applicable

Normnfc.nlp

Not applicable

45,794

13-Nov-2018

19:27

Not applicable

Normnfd.nlp

Not applicable

39,284

13-Nov-2018

19:27

Not applicable

Normnfkc.nlp

Not applicable

66,384

13-Nov-2018

19:27

Not applicable

Normnfkd.nlp

Not applicable

60,294

13-Nov-2018

19:27

Not applicable

Prc.nlp

Not applicable

83,748

13-Nov-2018

19:27

Not applicable

Prcp.nlp

Not applicable

83,748

13-Nov-2018

19:27

Not applicable

Sortkey.nlp

Not applicable

262,148

13-Nov-2018

19:27

Not applicable

Sorttbls.nlp

Not applicable

20,320

13-Nov-2018

19:27

Not applicable

Xjis.nlp

Not applicable

28,288

13-Nov-2018

19:27

Not applicable

Mscordacwks.dll

2.0.50727.8805

990,360

05-Feb-2019

14:06

x86

Mscorwks.dll

2.0.50727.8805

5,947,032

05-Feb-2019

14:06

x86

Sos.dll

2.0.50727.8805

389,784

05-Feb-2019

14:06

x86

x86 Windows 7

File name

File version

File size

Date

Time

Platform

Big5.nlp

Not applicable

66,728

13-Nov-2018

19:25

Not applicable

Bopomofo.nlp

Not applicable

82,172

13-Nov-2018

19:25

Not applicable

Ksc.nlp

Not applicable

116,756

13-Nov-2018

19:26

Not applicable

Mscorlib.dll

2.0.50727.8805

4,558,848

05-Feb-2019

14:06

x86

Normidna.nlp

Not applicable

59,342

13-Nov-2018

19:27

Not applicable

Normnfc.nlp

Not applicable

45,794

13-Nov-2018

19:27

Not applicable

Normnfd.nlp

Not applicable

39,284

13-Nov-2018

19:27

Not applicable

Normnfkc.nlp

Not applicable

66,384

13-Nov-2018

19:27

Not applicable

Normnfkd.nlp

Not applicable

60,294

13-Nov-2018

19:27

Not applicable

Prc.nlp

Not applicable

83,748

13-Nov-2018

19:27

Not applicable

Prcp.nlp

Not applicable

83,748

13-Nov-2018

19:27

Not applicable

Sortkey.nlp

Not applicable

262,148

13-Nov-2018

19:27

Not applicable

Sorttbls.nlp

Not applicable

20,320

13-Nov-2018

19:27

Not applicable

Xjis.nlp

Not applicable

28,288

13-Nov-2018

19:27

Not applicable

Mscordacwks.dll

2.0.50727.8805

990,360

05-Feb-2019

14:06

x86

Mscorwks.dll

2.0.50727.8805

5,947,032

05-Feb-2019

14:06

x86

Sos.dll

2.0.50727.8805

389,784

05-Feb-2019

14:06

x86

ia64 Windows Server 2008 R2

File property

Value

Ia64_49edebda559297a148b006b1746795e7_b03f5f7f11d50a3a_6.1.7601.24378_none_6bac8401a5800d36.manifest

Not applicable

908

05-Feb-2019

21:13

Not applicable

Ia64_4bedd950c10c2b53f3617dbb13010050_b03f5f7f11d50a3a_6.1.7601.24378_none_dd365e2003713545.manifest

Not applicable

916

05-Feb-2019

21:13

Not applicable

Ia64_93f88d6375ad829a1de3b3b79f2fc61c_b03f5f7f11d50a3a_6.1.7601.24378_none_be4b3dc1fb59a7bf.manifest

Not applicable

918

05-Feb-2019

21:13

Not applicable

Ia64_a5a40e651c52a56ca91f96612a9d1f29_b77a5c561934e089_6.1.7601.24378_none_454183dcf8318aea.manifest

Not applicable

898

05-Feb-2019

21:13

Not applicable

Ia64_a938b40f51b9db07db01166d6d62c341_b77a5c561934e089_6.1.7601.24378_none_f483e05390c4912a.manifest

Not applicable

626

05-Feb-2019

21:13

Not applicable

Ia64_mscorlib_b77a5c561934e089_6.1.7601.24378_none_854ac50b97a157f2.manifest

Not applicable

332,424

05-Feb-2019

16:16

Not applicable

Ia64_netfx-mscordacwks_b03f5f7f11d50a3a_6.1.7601.24378_none_e8b5b6dfdd29c84a.manifest

Not applicable

2,689

05-Feb-2019

16:15

Not applicable

Ia64_netfx-mscorwks_dll_b03f5f7f11d50a3a_6.1.7601.24378_none_eff193f90528bc77.manifest

Not applicable

6,590

05-Feb-2019

16:16

Not applicable

Ia64_netfx-sos_dll_b03f5f7f11d50a3a_6.1.7601.24378_none_d183fea0d11ea45f.manifest

Not applicable

2,009

05-Feb-2019

16:15

Not applicable

Msil_mscorlib.resources_b77a5c561934e089_6.1.7601.24378_en-us_4fbd223e8f6d8276.manifest

Not applicable

455

05-Feb-2019

15:50

Not applicable

Update.mum

Not applicable

2,189

05-Feb-2019

21:13

Not applicable

X86_mscorlib_b77a5c561934e089_6.1.7601.24378_none_854ae74997a1200e.manifest

Not applicable

299,131

05-Feb-2019

16:28

Not applicable

X86_netfx-mscordacwks_b03f5f7f11d50a3a_6.1.7601.24378_none_e8b5d91ddd299066.manifest

Not applicable

2,682

05-Feb-2019

16:29

Not applicable

X86_netfx-mscorwks_dll_b03f5f7f11d50a3a_6.1.7601.24378_none_eff1b63705288493.manifest

Not applicable

6,587

05-Feb-2019

16:28

Not applicable

X86_netfx-sos_dll_b03f5f7f11d50a3a_6.1.7601.24378_none_d18420ded11e6c7b.manifest

Not applicable

2,006

05-Feb-2019

16:27

Not applicable

x64 Windows 7 and Windows Server 2008 R2

File property

Value

Amd64_1d14034c434e3b7d68e0715158f70462_b03f5f7f11d50a3a_6.1.7601.24378_none_2d8666211717c797.manifest

Not applicable

625

05-Feb-2019

21:15

Not applicable

Amd64_7ee4df2d94fc311c4f39479b734605f7_b77a5c561934e089_6.1.7601.24378_none_f92d602da9c57753.manifest

Not applicable

620

05-Feb-2019

21:15

Not applicable

Amd64_8ad106366f6c3fdf25dec936b251a5ac_b03f5f7f11d50a3a_6.1.7601.24378_none_4785f513ea1ba77c.manifest

Not applicable

627

05-Feb-2019

21:15

Not applicable

Amd64_970d3f8ecbc7a485d695e3fa0b0158c1_b03f5f7f11d50a3a_6.1.7601.24378_none_5af07c535e89ea36.manifest

Not applicable

910

05-Feb-2019

21:15

Not applicable

Amd64_a938b40f51b9db07db01166d6d62c341_b77a5c561934e089_6.1.7601.24378_none_50a0d7e14923f964.manifest

Not applicable

627

05-Feb-2019

21:15

Not applicable

Amd64_c9dccc3ead5c1bc736df7401ab6822c1_b03f5f7f11d50a3a_6.1.7601.24378_none_a2ab475051032d77.manifest

Not applicable

630

05-Feb-2019

21:15

Not applicable

Amd64_cd8f842ce61092fd140cfeb7dac871b6_b03f5f7f11d50a3a_6.1.7601.24378_none_95709196cf1f8e81.manifest

Not applicable

623

05-Feb-2019

21:15

Not applicable

Amd64_d863ca3dc147eb2a7a1363f1fdab245d_b77a5c561934e089_6.1.7601.24378_none_44d0b2203d06f0cf.manifest

Not applicable

618

05-Feb-2019

21:15

Not applicable

Amd64_e6b89b9f55dfed6ac2cf3172f8231055_b77a5c561934e089_6.1.7601.24378_none_af0ef5bc74dd888a.manifest

Not applicable

900

05-Feb-2019

21:15

Not applicable

Amd64_e9421752675980378189e2aaf63d1b16_b03f5f7f11d50a3a_6.1.7601.24378_none_ef6954c7c1f7149a.manifest

Not applicable

629

05-Feb-2019

21:15

Not applicable

Amd64_ef4eaa54378cac13b9421c4ec786f8d6_b03f5f7f11d50a3a_6.1.7601.24378_none_8b3922bafb4e0c7c.manifest

Not applicable

628

05-Feb-2019

21:15

Not applicable

Amd64_f221b1597b1614cbe1611d10646c8788_b03f5f7f11d50a3a_6.1.7601.24378_none_90441e85b3e824a3.manifest

Not applicable

920

05-Feb-2019

21:15

Not applicable

Amd64_f94bf0d9e81e95fc067e3f59fdeaa755_b03f5f7f11d50a3a_6.1.7601.24378_none_4f1646f157b37b21.manifest

Not applicable

918

05-Feb-2019

21:15

Not applicable

Amd64_mscorlib_b77a5c561934e089_6.1.7601.24378_none_3d9db0728324f708.manifest

Not applicable

332,425

05-Feb-2019

16:37

Not applicable

Amd64_netfx-mscordacwks_b03f5f7f11d50a3a_6.1.7601.24378_none_a108a246c8ad6760.manifest

Not applicable

2,690

05-Feb-2019

16:38

Not applicable

Amd64_netfx-mscorwks_dll_b03f5f7f11d50a3a_6.1.7601.24378_none_a8447f5ff0ac5b8d.manifest

Not applicable

6,591

05-Feb-2019

16:37

Not applicable

Amd64_netfx-sos_dll_b03f5f7f11d50a3a_6.1.7601.24378_none_89d6ea07bca24375.manifest

Not applicable

2,010

05-Feb-2019

16:36

Not applicable

Msil_mscorlib.resources_b77a5c561934e089_6.1.7601.24378_en-us_4fbd223e8f6d8276.manifest

Not applicable

455

05-Feb-2019

16:14

Not applicable

Update.mum

Not applicable

3,167

05-Feb-2019

21:15

Not applicable

X86_mscorlib_b77a5c561934e089_6.1.7601.24378_none_854ae74997a1200e.manifest

Not applicable

299,131

05-Feb-2019

16:28

Not applicable

X86_netfx-mscordacwks_b03f5f7f11d50a3a_6.1.7601.24378_none_e8b5d91ddd299066.manifest

Not applicable

2,682

05-Feb-2019

16:29

Not applicable

X86_netfx-mscorwks_dll_b03f5f7f11d50a3a_6.1.7601.24378_none_eff1b63705288493.manifest

Not applicable

6,587

05-Feb-2019

16:28

Not applicable

X86_netfx-sos_dll_b03f5f7f11d50a3a_6.1.7601.24378_none_d18420ded11e6c7b.manifest

Not applicable

2,006

05-Feb-2019

16:27

Not applicable

x86 Windows 7

File property

Value

Msil_mscorlib.resources_b77a5c561934e089_6.1.7601.24378_en-us_4fbd223e8f6d8276.manifest

Not applicable

455

05-Feb-2019

16:09

Not applicable

Update.mum

Not applicable

2,303

05-Feb-2019

21:13

Not applicable

X86_8ad106366f6c3fdf25dec936b251a5ac_b03f5f7f11d50a3a_6.1.7601.24378_none_eb67599031be3646.manifest

Not applicable

625

05-Feb-2019

21:13

Not applicable

X86_a938b40f51b9db07db01166d6d62c341_b77a5c561934e089_6.1.7601.24378_none_f4823c5d90c6882e.manifest

Not applicable

625

05-Feb-2019

21:13

Not applicable

X86_cd8f842ce61092fd140cfeb7dac871b6_b03f5f7f11d50a3a_6.1.7601.24378_none_3951f61316c21d4b.manifest

Not applicable

621

05-Feb-2019

21:13

Not applicable

X86_d863ca3dc147eb2a7a1363f1fdab245d_b77a5c561934e089_6.1.7601.24378_none_e8b2169c84a97f99.manifest

Not applicable

616

05-Feb-2019

21:13

Not applicable

X86_ef4eaa54378cac13b9421c4ec786f8d6_b03f5f7f11d50a3a_6.1.7601.24378_none_2f1a873742f09b46.manifest

Not applicable

626

05-Feb-2019

21:13

Not applicable

X86_mscorlib_b77a5c561934e089_6.1.7601.24378_none_854ae74997a1200e.manifest

Not applicable

299,131

05-Feb-2019

16:28

Not applicable

X86_netfx-mscordacwks_b03f5f7f11d50a3a_6.1.7601.24378_none_e8b5d91ddd299066.manifest

Not applicable

2,682

05-Feb-2019

16:29

Not applicable

X86_netfx-mscorwks_dll_b03f5f7f11d50a3a_6.1.7601.24378_none_eff1b63705288493.manifest

Not applicable

6,587

05-Feb-2019

16:28

Not applicable

X86_netfx-sos_dll_b03f5f7f11d50a3a_6.1.7601.24378_none_d18420ded11e6c7b.manifest

Not applicable

2,006

05-Feb-2019

16:27

Not applicable

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