Applies ToWindows 10, version 2004, all editions Windows 10, version 20H2, all editions

Summary

This update makes improvements to the "Safe OS" that is used to update the Windows recovery environment (WinRE) for Windows 10, version 2004 and 20H2.

How to get this update

This update is available through Windows Update. It will be downloaded and installed automatically.

Prerequisites 

There are no prerequisites to apply this update. 

Restart information 

You don't have to restart your device after you apply this update.  

Update replacement information 

  • For Windows 10, version 2004, this update replaces the previously released update KB4579305.

  • For Windows 10, version 20H2, this update does not replace any previously released update.

File information

File attributes

The English (United States) version of this software update installs files that have the attributes that are listed in the following tables.

File verification

File hash information

File name

SHA1 hash

SHA256 hash

Windows10.0-KB4586858-x86.msu

EEF391495ABE6DD1B9B9288EE6A19FB8DEEBAF73

648C5E2E6A72996418B150E42B7283C9C76265EFC209CBE83483E552A42E55F7

Windows10.0-KB4586858-x64.msu

8713EE767680867DDCADA8C85165C06A07DA4D68

EC37BF1CD31573276E26B1552B63D146FB9C60BBB59028E624E28BF0F19D40F0

Windows10.0-KB4586858-arm64.msu

5C94BADAC0D9929794DB1185A826F05495623729

93DD13B908EC4023C30485DC0A803A5681D08669F3EDD88F7309F831A58E5B0B

For all supported x86-based versions

File name

File size

Date

Time

Bootux.dll

5,322

19-Oct-2020

09:06

Bootux.dll

5,417

19-Oct-2020

09:06

Bootux.dll.mui

323

19-Oct-2020

09:06

Bootux.dll.mui

331

19-Oct-2020

09:06

Bootim.exe

243

19-Oct-2020

09:06

Bootux.dll

5,322

19-Oct-2020

09:06

Bootim.exe

238

19-Oct-2020

09:06

Bootux.dll

5,417

19-Oct-2020

09:06

Cmi2migxml.dll

1,914

19-Oct-2020

09:06

Csiagent.dll

1,995

19-Oct-2020

09:06

Diager.dll

1,976

19-Oct-2020

09:06

Hwcompat.dll

1,914

19-Oct-2020

09:06

Migapp.xml

54

19-Oct-2020

09:06

Migcore.dll

56,474

19-Oct-2020

09:07

Mighost.exe

1,911

19-Oct-2020

09:06

Migisol.dll

1,915

19-Oct-2020

09:06

Migres.dll

1,957

19-Oct-2020

09:06

Migstore.dll

2,491

19-Oct-2020

09:06

Migsys.dll

1,920

19-Oct-2020

09:06

Mxeagent.dll

1,908

19-Oct-2020

09:06

Offline.xml

52

19-Oct-2020

09:06

Oscomps.woa.xml

54

19-Oct-2020

09:06

Oscomps.xml

54

19-Oct-2020

09:06

Pnppropmig.dll

2,068

19-Oct-2020

09:06

Reagent.dll

3,080

19-Oct-2020

09:06

Reservemanager.dll

3,835

19-Oct-2020

09:06

Setupplatform.cfg

51

19-Oct-2020

09:06

Setupplatform.dll

76,729

19-Oct-2020

09:07

Setupplatform.exe

1,971

19-Oct-2020

09:06

Sfcn.dat

50

19-Oct-2020

09:06

Sflcid.dat

50

19-Oct-2020

09:06

Sflistrs1.dat

55

19-Oct-2020

09:06

Sflistw7.dat

54

19-Oct-2020

09:06

Sflistw8.dat

55

19-Oct-2020

09:06

Sflistw8.woa.dat

54

19-Oct-2020

09:06

Sflistwb.dat

55

19-Oct-2020

09:06

Sflistwb.woa.dat

54

19-Oct-2020

09:06

Sflistwt.dat

55

19-Oct-2020

09:06

Sflistwt.woa.dat

55

19-Oct-2020

09:06

Unbcl.dll

1,995

19-Oct-2020

09:06

Uninstall.xml

50

19-Oct-2020

09:06

Uninstall_data.xml

52

19-Oct-2020

09:06

Upgradeagent.dll

1,974

19-Oct-2020

09:06

Upgradeagent.xml

53

19-Oct-2020

09:06

Upgrade_bulk.xml

54

19-Oct-2020

09:06

Upgrade_comp.xml

51

19-Oct-2020

09:06

Upgrade_data.xml

52

19-Oct-2020

09:06

Upgrade_frmwrk.xml

52

19-Oct-2020

09:06

Upgwow_bulk.xml

53

19-Oct-2020

09:06

Wdsutil.dll

2,008

19-Oct-2020

09:06

Cmi2migxml.dll

1,897

19-Oct-2020

09:06

Csiagent.dll

1,984

19-Oct-2020

09:06

Diager.dll

1,952

19-Oct-2020

09:06

Hwcompat.dll

1,893

19-Oct-2020

09:06

Migapp.xml

54

19-Oct-2020

09:06

Migcore.dll

56,356

19-Oct-2020

09:07

Mighost.exe

1,903

19-Oct-2020

09:06

Migisol.dll

1,894

19-Oct-2020

09:06

Migres.dll

1,941

19-Oct-2020

09:06

Migstore.dll

2,473

19-Oct-2020

09:06

Migsys.dll

1,903

19-Oct-2020

09:06

Mxeagent.dll

1,898

19-Oct-2020

09:06

Offline.xml

52

19-Oct-2020

09:06

Oscomps.woa.xml

54

19-Oct-2020

09:06

Oscomps.xml

54

19-Oct-2020

09:06

Pnppropmig.dll

2,047

19-Oct-2020

09:06

Reagent.dll

3,047

19-Oct-2020

09:06

Reservemanager.dll

3,726

19-Oct-2020

09:06

Setupplatform.cfg

51

19-Oct-2020

09:06

Setupplatform.dll

75,562

19-Oct-2020

09:07

Setupplatform.exe

1,953

19-Oct-2020

09:06

Sfcn.dat

50

19-Oct-2020

09:06

Sflcid.dat

50

19-Oct-2020

09:06

Sflistrs1.dat

55

19-Oct-2020

09:06

Sflistw7.dat

54

19-Oct-2020

09:06

Sflistw8.dat

55

19-Oct-2020

09:06

Sflistw8.woa.dat

54

19-Oct-2020

09:06

Sflistwb.dat

55

19-Oct-2020

09:06

Sflistwb.woa.dat

54

19-Oct-2020

09:06

Sflistwt.dat

55

19-Oct-2020

09:06

Sflistwt.woa.dat

55

19-Oct-2020

09:06

Unbcl.dll

1,979

19-Oct-2020

09:06

Uninstall.xml

50

19-Oct-2020

09:06

Uninstall_data.xml

52

19-Oct-2020

09:06

Upgradeagent.dll

1,971

19-Oct-2020

09:06

Upgradeagent.xml

53

19-Oct-2020

09:06

Upgrade_bulk.xml

54

19-Oct-2020

09:06

Upgrade_comp.xml

51

19-Oct-2020

09:06

Upgrade_data.xml

52

19-Oct-2020

09:06

Upgrade_frmwrk.xml

52

19-Oct-2020

09:06

Upgwow_bulk.xml

53

19-Oct-2020

09:06

Wdsutil.dll

1,983

19-Oct-2020

09:06

Reseteng.dll

4,955

19-Oct-2020

09:06

Resetengine.dll

22,773

19-Oct-2020

09:06

Resetengine.exe

2,740

19-Oct-2020

09:06

Resetenginterfaces.exe

266

19-Oct-2020

09:06

Resetengmig.dll

471

19-Oct-2020

09:06

Resetpluginhost.exe

316

19-Oct-2020

09:06

Srms.dat

52

19-Oct-2020

09:06

Srms62.dat

52

19-Oct-2020

09:06

Sysreset.exe

3,109

19-Oct-2020

09:06

Reseteng.dll

3,817

19-Oct-2020

09:06

Resetengine.dll

20,576

19-Oct-2020

09:06

Resetengine.exe

2,915

19-Oct-2020

09:06

Resetenginterfaces.exe

260

19-Oct-2020

09:06

Resetengmig.dll

467

19-Oct-2020

09:06

Resetpluginhost.exe

310

19-Oct-2020

09:06

Srms.dat

52

19-Oct-2020

09:06

Srms62.dat

52

19-Oct-2020

09:06

Sysreset.exe

2,085

19-Oct-2020

09:06

For all supported x64-based versions

File name

File size

Date

Time

Bootux.dll

6,435

19-Oct-2020

09:08

Bootux.dll

6,556

19-Oct-2020

09:08

Bootux.dll.mui

323

19-Oct-2020

09:08

Bootux.dll.mui

331

19-Oct-2020

09:08

Bootim.exe

242

19-Oct-2020

09:08

Bootux.dll

6,435

19-Oct-2020

09:08

Bootim.exe

239

19-Oct-2020

09:08

Bootux.dll

6,556

19-Oct-2020

09:08

Cmi2migxml.dll

1,995

19-Oct-2020

09:08

Csiagent.dll

2,082

19-Oct-2020

09:08

Diager.dll

2,055

19-Oct-2020

09:08

Hwcompat.dll

1,993

19-Oct-2020

09:08

Migapp.xml

54

19-Oct-2020

09:08

Migcore.dll

153,869

19-Oct-2020

09:09

Mighost.exe

1,984

19-Oct-2020

09:08

Migisol.dll

1,968

19-Oct-2020

09:08

Migres.dll

1,965

19-Oct-2020

09:08

Migstore.dll

18,391

19-Oct-2020

09:08

Migsys.dll

2,000

19-Oct-2020

09:08

Mxeagent.dll

1,996

19-Oct-2020

09:08

Offline.xml

52

19-Oct-2020

09:08

Oscomps.woa.xml

54

19-Oct-2020

09:08

Oscomps.xml

54

19-Oct-2020

09:08

Pnppropmig.dll

2,105

19-Oct-2020

09:08

Reagent.dll

3,740

19-Oct-2020

09:08

Reservemanager.dll

5,602

19-Oct-2020

09:08

Setupplatform.cfg

51

19-Oct-2020

09:08

Setupplatform.dll

210,965

19-Oct-2020

09:09

Setupplatform.exe

2,073

19-Oct-2020

09:08

Sfcn.dat

50

19-Oct-2020

09:08

Sflcid.dat

50

19-Oct-2020

09:08

Sflistrs1.dat

55

19-Oct-2020

09:08

Sflistw7.dat

54

19-Oct-2020

09:08

Sflistw8.dat

55

19-Oct-2020

09:08

Sflistw8.woa.dat

54

19-Oct-2020

09:08

Sflistwb.dat

55

19-Oct-2020

09:08

Sflistwb.woa.dat

54

19-Oct-2020

09:08

Sflistwt.dat

55

19-Oct-2020

09:08

Sflistwt.woa.dat

55

19-Oct-2020

09:08

Unbcl.dll

2,098

19-Oct-2020

09:08

Uninstall.xml

50

19-Oct-2020

09:08

Uninstall_data.xml

52

19-Oct-2020

09:08

Upgradeagent.dll

2,012

19-Oct-2020

09:08

Upgradeagent.xml

53

19-Oct-2020

09:08

Upgrade_bulk.xml

54

19-Oct-2020

09:08

Upgrade_comp.xml

51

19-Oct-2020

09:08

Upgrade_data.xml

52

19-Oct-2020

09:08

Upgrade_frmwrk.xml

52

19-Oct-2020

09:08

Upgwow_bulk.xml

53

19-Oct-2020

09:08

Wdsutil.dll

2,094

19-Oct-2020

09:08

Cmi2migxml.dll

1,981

19-Oct-2020

09:08

Csiagent.dll

2,069

19-Oct-2020

09:08

Diager.dll

2,033

19-Oct-2020

09:08

Hwcompat.dll

1,987

19-Oct-2020

09:08

Migapp.xml

54

19-Oct-2020

09:08

Migcore.dll

153,582

19-Oct-2020

09:09

Mighost.exe

1,972

19-Oct-2020

09:08

Migisol.dll

1,975

19-Oct-2020

09:08

Migres.dll

1,957

19-Oct-2020

09:08

Migstore.dll

18,181

19-Oct-2020

09:08

Migsys.dll

1,986

19-Oct-2020

09:08

Mxeagent.dll

1,984

19-Oct-2020

09:08

Offline.xml

52

19-Oct-2020

09:08

Oscomps.woa.xml

54

19-Oct-2020

09:08

Oscomps.xml

54

19-Oct-2020

09:08

Pnppropmig.dll

2,087

19-Oct-2020

09:08

Reagent.dll

3,689

19-Oct-2020

09:08

Reservemanager.dll

5,025

19-Oct-2020

09:08

Setupplatform.cfg

51

19-Oct-2020

09:08

Setupplatform.dll

212,041

19-Oct-2020

09:09

Setupplatform.exe

2,059

19-Oct-2020

09:08

Sfcn.dat

50

19-Oct-2020

09:08

Sflcid.dat

50

19-Oct-2020

09:08

Sflistrs1.dat

55

19-Oct-2020

09:08

Sflistw7.dat

54

19-Oct-2020

09:08

Sflistw8.dat

55

19-Oct-2020

09:08

Sflistw8.woa.dat

54

19-Oct-2020

09:08

Sflistwb.dat

55

19-Oct-2020

09:08

Sflistwb.woa.dat

54

19-Oct-2020

09:08

Sflistwt.dat

55

19-Oct-2020

09:08

Sflistwt.woa.dat

55

19-Oct-2020

09:08

Unbcl.dll

2,085

19-Oct-2020

09:08

Uninstall.xml

50

19-Oct-2020

09:08

Uninstall_data.xml

52

19-Oct-2020

09:08

Upgradeagent.dll

1,995

19-Oct-2020

09:08

Upgradeagent.xml

53

19-Oct-2020

09:08

Upgrade_bulk.xml

54

19-Oct-2020

09:08

Upgrade_comp.xml

51

19-Oct-2020

09:08

Upgrade_data.xml

52

19-Oct-2020

09:08

Upgrade_frmwrk.xml

52

19-Oct-2020

09:08

Upgwow_bulk.xml

53

19-Oct-2020

09:08

Wdsutil.dll

2,070

19-Oct-2020

09:08

Reseteng.dll

8,569

19-Oct-2020

09:08

Resetengine.dll

96,085

19-Oct-2020

09:08

Resetengine.exe

2,834

19-Oct-2020

09:08

Resetenginterfaces.exe

416

19-Oct-2020

09:08

Resetengmig.dll

951

19-Oct-2020

09:08

Resetpluginhost.exe

581

19-Oct-2020

09:08

Srms.dat

52

19-Oct-2020

09:08

Srms62.dat

52

19-Oct-2020

09:08

Sysreset.exe

4,994

19-Oct-2020

09:08

Reseteng.dll

7,123

19-Oct-2020

09:08

Resetengine.dll

93,714

19-Oct-2020

09:08

Resetengine.exe

2,806

19-Oct-2020

09:08

Resetenginterfaces.exe

391

19-Oct-2020

09:08

Resetengmig.dll

887

19-Oct-2020

09:08

Resetpluginhost.exe

562

19-Oct-2020

09:08

Srms.dat

52

19-Oct-2020

09:08

Srms62.dat

52

19-Oct-2020

09:08

Sysreset.exe

3,617

19-Oct-2020

09:08

For all supported ARM-based versions

File name

File size

Date

Time

Bootux.dll

7,568

19-Oct-2020

09:07

Bootux.dll

7,662

19-Oct-2020

09:07

Bootux.dll.mui

323

19-Oct-2020

09:06

Bootux.dll.mui

331

19-Oct-2020

09:06

Bootim.exe

246

19-Oct-2020

09:06

Bootux.dll

7,568

19-Oct-2020

09:07

Bootim.exe

241

19-Oct-2020

09:07

Bootux.dll

7,662

19-Oct-2020

09:07

Cmi2migxml.dll

1,914

19-Oct-2020

09:07

Csiagent.dll

2,005

19-Oct-2020

09:07

Diager.dll

1,234

19-Oct-2020

09:07

Hwcompat.dll

1,912

19-Oct-2020

09:07

Migapp.xml

54

19-Oct-2020

09:07

Migcore.dll

470,447

19-Oct-2020

09:08

Mighost.exe

1,965

19-Oct-2020

09:07

Migisol.dll

1,973

19-Oct-2020

09:07

Migres.dll

1,993

19-Oct-2020

09:07

Migstore.dll

38,762

19-Oct-2020

09:07

Migsys.dll

1,920

19-Oct-2020

09:07

Mxeagent.dll

2,085

19-Oct-2020

09:07

Offline.xml

52

19-Oct-2020

09:07

Oscomps.woa.xml

54

19-Oct-2020

09:07

Oscomps.xml

54

19-Oct-2020

09:07

Pnppropmig.dll

2,001

19-Oct-2020

09:07

Reagent.dll

10,168

19-Oct-2020

09:07

Reservemanager.dll

9,275

19-Oct-2020

09:07

Setupplatform.cfg

51

19-Oct-2020

09:07

Setupplatform.dll

405,315

19-Oct-2020

09:07

Setupplatform.exe

2,320

19-Oct-2020

09:07

Sfcn.dat

50

19-Oct-2020

09:07

Sflcid.dat

50

19-Oct-2020

09:07

Sflistrs1.dat

55

19-Oct-2020

09:07

Sflistw7.dat

54

19-Oct-2020

09:07

Sflistw8.dat

55

19-Oct-2020

09:07

Sflistw8.woa.dat

54

19-Oct-2020

09:07

Sflistwb.dat

55

19-Oct-2020

09:07

Sflistwb.woa.dat

54

19-Oct-2020

09:07

Sflistwt.dat

55

19-Oct-2020

09:07

Sflistwt.woa.dat

55

19-Oct-2020

09:07

Unbcl.dll

2,189

19-Oct-2020

09:07

Uninstall.xml

50

19-Oct-2020

09:07

Uninstall_data.xml

52

19-Oct-2020

09:07

Upgradeagent.dll

1,927

19-Oct-2020

09:07

Upgradeagent.xml

53

19-Oct-2020

09:07

Upgrade_bulk.xml

54

19-Oct-2020

09:07

Upgrade_comp.xml

51

19-Oct-2020

09:07

Upgrade_data.xml

52

19-Oct-2020

09:07

Upgrade_frmwrk.xml

52

19-Oct-2020

09:07

Upgwowa32_bulk.xml

53

19-Oct-2020

09:07

Upgwow_bulk.xml

53

19-Oct-2020

09:07

Wdsutil.dll

2,012

19-Oct-2020

09:07

Cmi2migxml.dll

1,890

19-Oct-2020

09:07

Csiagent.dll

1,982

19-Oct-2020

09:07

Diager.dll

1,227

19-Oct-2020

09:07

Hwcompat.dll

1,893

19-Oct-2020

09:07

Migapp.xml

54

19-Oct-2020

09:07

Migcore.dll

463,207

19-Oct-2020

09:08

Mighost.exe

1,956

19-Oct-2020

09:07

Migisol.dll

1,972

19-Oct-2020

09:07

Migres.dll

1,986

19-Oct-2020

09:07

Migstore.dll

38,886

19-Oct-2020

09:07

Migsys.dll

1,905

19-Oct-2020

09:07

Mxeagent.dll

2,268

19-Oct-2020

09:07

Offline.xml

52

19-Oct-2020

09:07

Oscomps.woa.xml

54

19-Oct-2020

09:07

Oscomps.xml

54

19-Oct-2020

09:07

Pnppropmig.dll

2,008

19-Oct-2020

09:07

Reagent.dll

10,092

19-Oct-2020

09:07

Reservemanager.dll

8,928

19-Oct-2020

09:07

Setupplatform.cfg

51

19-Oct-2020

09:07

Setupplatform.dll

407,053

19-Oct-2020

09:08

Setupplatform.exe

2,133

19-Oct-2020

09:07

Sfcn.dat

50

19-Oct-2020

09:07

Sflcid.dat

50

19-Oct-2020

09:07

Sflistrs1.dat

55

19-Oct-2020

09:07

Sflistw7.dat

54

19-Oct-2020

09:07

Sflistw8.dat

55

19-Oct-2020

09:07

Sflistw8.woa.dat

54

19-Oct-2020

09:07

Sflistwb.dat

55

19-Oct-2020

09:07

Sflistwb.woa.dat

54

19-Oct-2020

09:07

Sflistwt.dat

55

19-Oct-2020

09:07

Sflistwt.woa.dat

55

19-Oct-2020

09:07

Unbcl.dll

2,366

19-Oct-2020

09:07

Uninstall.xml

50

19-Oct-2020

09:07

Uninstall_data.xml

52

19-Oct-2020

09:07

Upgradeagent.dll

1,909

19-Oct-2020

09:07

Upgradeagent.xml

53

19-Oct-2020

09:07

Upgrade_bulk.xml

54

19-Oct-2020

09:07

Upgrade_comp.xml

51

19-Oct-2020

09:07

Upgrade_data.xml

52

19-Oct-2020

09:07

Upgrade_frmwrk.xml

52

19-Oct-2020

09:07

Upgwowa32_bulk.xml

53

19-Oct-2020

09:07

Upgwow_bulk.xml

53

19-Oct-2020

09:07

Wdsutil.dll

1,981

19-Oct-2020

09:07

Reseteng.dll

38,707

19-Oct-2020

09:07

Resetengine.dll

170,547

19-Oct-2020

09:07

Resetengine.exe

2,731

19-Oct-2020

09:07

Resetenginterfaces.exe

260

19-Oct-2020

09:07

Resetengmig.dll

954

19-Oct-2020

09:07

Resetpluginhost.exe

310

19-Oct-2020

09:07

Srms.dat

52

19-Oct-2020

09:07

Srms62.dat

52

19-Oct-2020

09:07

Sysreset.exe

11,371

19-Oct-2020

09:07

Reseteng.dll

37,886

19-Oct-2020

09:07

Resetengine.dll

169,112

19-Oct-2020

09:07

Resetengine.exe

2,925

19-Oct-2020

09:07

Resetenginterfaces.exe

255

19-Oct-2020

09:07

Resetengmig.dll

943

19-Oct-2020

09:07

Resetpluginhost.exe

306

19-Oct-2020

09:07

Srms.dat

52

19-Oct-2020

09:07

Srms62.dat

52

19-Oct-2020

09:07

Sysreset.exe

10,317

19-Oct-2020

09:07

References

The benefits of Windows 10 Dynamic Update

Updating Windows 10 media with Dynamic Update packages

Learn about the terminology that Microsoft uses to describe software updates.

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