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Summary

This update provides a compatibility fix to Windows Setup in Windows 10, version 2004, 20H2, and 21H1. This compatibility fix enables an in-place upgrade to be run on devices that cannot complete the installation of the latest cumulative update (LCU).

Known issues in this update

We are currently not aware of any issues that affect this update.

How to get this update

Microsoft Update Catalog

Release Channel

Available

Next Step

Microsoft Update Catalog

Yes

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

Windows Server Update Services (WSUS)

Yes

You can import this update into WSUS manually. For more information, see the Frequently Asked Questions topic on the Microsoft Update Catalog website for instructions.

Prerequisites 

There are no prerequisites to apply this update.

Restart information 

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

Update replacement information 

This update does not replace any 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 times for these files are listed in Coordinated Universal Time (UTC). The dates and 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 times may change when you perform certain operations on the files.

File name

File version

Date

Time

File size

sysmain.sdb

Not versioned

16-Aug-2021

21:25

3,873,652

AcRes.dll

10.0.19041.1255

16-Aug-2021

21:25

332,616

AcXtrnal.dll

10.0.19041.1255

17-Aug-2021

0:48

86,528

AcLayers.dll

10.0.19041.1255

17-Aug-2021

0:43

381,440

File name

File version

Date

Time

File size

sysmain.sdb

Not versioned

17-Aug-2021

1:12

4,060,054

AcRes.dll

10.0.19041.1255

17-Aug-2021

1:12

332,624

AcXtrnal.dll

10.0.19041.1255

17-Aug-2021

5:05

15,872

AcLayers.dll

10.0.19041.1255

17-Aug-2021

4:47

326,144

AcXtrnal.dll

10.0.19041.1255

17-Aug-2021

0:48

86,528

AcLayers.dll

10.0.19041.1255

17-Aug-2021

0:43

381,440

File name

File version

Date

Time

File size

AcXtrnal.dll

10.0.19041.1255

17-Aug-2021

1:45

32,768

AcLayers.dll

10.0.19041.1255

17-Aug-2021

1:45

32,768

AcXtrnal.dll

10.0.19041.1255

17-Aug-2021

0:48

86,528

AcLayers.dll

10.0.19041.1255

17-Aug-2021

0:43

381,440

sysmain.sdb

Not versioned

16-Aug-2021

22:03

4,059,266

AcRes.dll

10.0.19041.1255

16-Aug-2021

22:03

332,624

AcXtrnal.dll

10.0.19041.1255

17-Aug-2021

2:13

12,800

AcLayers.dll

10.0.19041.1255

17-Aug-2021

2:13

15,872

References

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

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