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Error 0x800B0100

Windows Update Error 0x800B0100

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Error 0x800B0100 usually appears in Windows Vista Operating Systems. If this error is on XP, this may appear if XP is being repair installed. Frequently, this is caused by either failed installations of updates or pending updates that required a reboot but did not complete causing a corruption in the DataStore files and files in the Servicing Packages folder. Seldom, it could be caused by Cryptographic errors, Corrupted Windows Update files, Service and Dependency services failing to start, incorrect Date and Time, Untrusted Publishers in the Certificates container, incorrect Security Settings in Internet Explorer, Corrupted files in the SoftwareDistribution Download folder or 3rd Party Security Software. Rarely, it can be a hardware failure for either the motherboard or peripheral components such as RAM and Graphics cards.

In resolving issues of 0x800B0100 requires two log files namely the CBS.LOG (Component-Based Servicing log) and the CHECKSUR.LOG (Check System Update Readiness log) without which we would not be able to recognize what files are corrupted or missing from the system. The CBS and CheckSUR logs are only available in Windows Vista platforms and not on Windows XP.


Creating the CBS.LOG would require running an SFC /SCANNOW and creating a CHECKSUR.LOG would require downloading the System Update Readiness Tool (KB947821). 



1.     Creating a CBS log:

a.     Running the System File Checker could resolve your issues altogether. SFC checks and resolves inconsistencies or corruption of the System files it found.

b.     Use SFC /SCANNOW on an elevated Command Prompt if you are using Vista.


2.     Running CheckSUR:

a.     The Windows Vista Check for System Update Readiness (CheckSUR) tool will try to fix certain Windows Update installation failures. System resources, such as file data, registry data, and even in-memory data, can develop inconsistencies during the lifetime of the operating system. These inconsistencies may be caused by various hardware failures or by software issues. In some cases, these inconsistencies can affect the Windows Servicing Store, and they can cause a Windows Vista update to fail. When the update fails, it blocks the user from installing updates and service packs. CheckSUR addresses this issue. When Windows Update detects inconsistencies that are related to system servicing in system files or in the registry, Windows Update offers CheckSUR as an available update package.

b.     To manually install and run CheckSUR, follow these steps:

·         Click Start, click All Programs, click Accessories, right-click Command Prompt, and then click Run as administrator.

·         In the User Account Control dialog box, click Continue.

·         Type REG ADD HKLMCOMPONENTS /v StoreCorruptTimeStamp /t REG_SZ /d “0” /f, and then press ENTER.

·         Type REG DELETE HKLMSOFTWAREMicrosoftWindowsCurrentVersionCheckSUR, and then press ENTER.

·         Download and then install CheckSUR from the Microsoft Download Center KB947821.

·         As soon as the file has been successfully downloaded, double-click the file to install and run CheckSUR.

·         We recommend that you restart your computer after you run CheckSUR to make sure that any changes take effect.

·         Additionally, you must try to reinstall any software updates that previously could not be installed.

·         If CheckSUR detected and fixed the cause of the failures, these updates will now install successfully.

·         If CheckSUR failed proceed to 3. Analysis is at step 4.


3.     Launching CBS or CHECKSUR logs using notepad:

a.     Open a Command Prompt, in Vista run Command Prompt as Administrator.

b.     For CBS.LOG, type in: Notepad %WINDIR%logsCBSCBS.log

c.     For CheckSUR.LOG, type in: Notepad %WINDIR%logsCBSCheckSUR.log


4.     Analyzing the CBS and CHECKSUR logs.

a.     In the CBS.log scroll to the bottom and use FIND in an upward direction and “Match Case” to look for the recent WER errors. This will point out errors for either corrupted services, components or missing files. Take note of the any failure or error. This will help you in troubleshooting the issue later. You should also see a “status: 0x800b0100, failure source: Execute, start state: 4, target state: 7” somewhere in the string which means you are looking at the specific file that is causing your issue. Make sure you collect all WER errors until the most recent date only. It may not only be one file but a set of files that may also have the same error string.


Sample CBS logs (excerpt):


CBS: Mark store corruption flag because of package:

Package_16_for_KB948465~31bf3856ad364e35~x86~~ hr: 0x800b0100

WER: Generating failure report for package: Package_for_KB905866~31bf3856ad364e35~x86~~, status: 0x800b0100, failure source: Execute, start state: 4, target state: 7


CBS: Mark store corruption flag because of package: Package_24_for_KB948465~31bf3856ad364e35~x86~~ hr: 0x800b0100

WER: Generating failure report for package: Package_for_KB961371~31bf3856ad364e35~x86~~, status: 0x800b0100, failure source: Execute, start state: 4, target state: 7


CBS: Mark store corruption flag because of package: Package_25_for_KB948465~31bf3856ad364e35~x86~~ hr: 0x800b0100

WER: Generating failure report for package: Package_for_KB961371~31bf3856ad364e35~x86~~, status: 0x800b0100, failure source: Execute, start state: 4, target state: 7


If you need more info on reading CBS logs Microsoft has a Knowledge Base entry for learning how to read CBS.log – http://support.microsoft.com/kb/928228.


The CheckSUR.log is a precise view of what files are causing your errors. CheckSUR was also designed to be able to resolve specific functionality and compatibility issues of Windows Update. If CheckSUR was not able to resolve the issue it will be due to missing files such as the .MUM (Microsoft Update Manifest) and the accompanied .CAT (Security Catalog) files. If you don’t have a CheckSUR log it will be advisable for you to download and run the Windows Update System Readiness Tool from http://support.microsoft.com/kb/947821 use the appropriate package for your platform (32bit or 64bit Note: CheckSUR only works for Vista and Windows 7 platforms and later!).


Sample CheckSUR logs:


Checking System Update Readiness.

Binary Version 6.0.6001.22375

Package Version 5.0

2009-07-15 23:02


Checking Deployment Packages


Checking Package Manifests and catalogs.


Checking package watchlist.


Checking component watchlist.


Checking packages.


(f) CBS MUM Missing 0x00000002 servicingpackagesPackage_16_for_KB948465~31bf3856ad364e35~x86~~

(f) CBS MUM Missing 0x00000002 servicingpackagesPackage_24_for_KB948465~31bf3856ad364e35~x86~~

(f) CBS MUM Missing 0x00000002 servicingpackagesPackage_25_for_KB948465~31bf3856ad364e35~x86~~


Checking component store


Seconds executed: 3749

Found 3 errors

CBS MUM Missing Total Count: 3


5.     Extracting files from *.MSU Stand-Alone installers of Vista and Update.exe or HotFix.exe for XP:

a.     Download the necessary package or update which needs to be replaced.

b.     Extract the files from the Stand-Alone installer.

·         Depending on what version of the Stand-Alone installer, there are different methods you may need to use to extract the files.

·         Using the Expand command line

·         For older versions: use the /extract or /x

·         For *.MSU: http://support.microsoft.com/kb/928636 contains Command Line switches available for Windows Update Stand-Alone (WUSA.EXE) installers or .MSU files.

·         For Update.exe or HotFix.exe: http://support.microsoft.com/kb/262841 contains a list of Command Line Switches for Stand-Alone packages for Updates and HotFixes.




For *.MSU:

·         Open Command Prompt in Elevated Mode.

·         Create a folder where the files of the .MSU package can be extracted to.

o    Type in: CD [PATH where .MSU file is located] e.g. CD %USERPROFILE%Desktop assuming you saved the .MSU file on the Desktop of the User Account.

o    Type in: Expand -F:* Saved_MSU_File_Name.msu “[PATH where files are to be extracted] e.g. Expand -F:* Windows6.0-x86-KB948465.msu “%USERPROFILE%DesktopKB948465” assuming you created a folder on the Desktop named KB948465 for the same package.


For Update.exe or HotFix.exe:

·         Open Command Prompt.

·         Create a folder where the files of the Update package can be extracted to.

o    Type in: CD [PATH where .MSU file is located] e.g. CD %USERPROFILE%Desktop assuming you saved the .MSU file on the Desktop of the User Account.

o    Type in: KBArticleNumber /extract:“[PATH where files are to be extracted]" e.g. WindowsXP-KB936929-SP3-x86-ENU.exe /extract:“%USERPROFILE%DesktopKB936929” assuming we need to extract the files into a KB936929 folder on the Desktop.

o    For packages created before July 2004 change the /extract to /X switch. To know if the /X switch is to be used you need to know if this is a Self-Extracting Cabinet. To do this, right-click on the file, choose Properties and under the General tab the Details should appear as a Self-Extracting Cabinet.


6.     Replacing Corrupted or Missing Packages found from CBS and CheckSUR logs:

a.     Copy the necessary files which are missing based on the CBS and CheckSUR logs. These files will be located inside the .CAB file from the package you just extracted.

b.     Include all of the *.MUM and its associated *.CAT file into %WINDIR%ServicingPackages.

c.     If you encounter an “Access is Denied” error Take Ownership of the folder and grant Full Access for the Administrators group. You may perform it using the Security tab or using this command line:

·         Open Command Prompt in Elevated Mode, then type in:

o    takeown /F <foldername> /R /D Y or in this case takeown /F “%WINDIR%ServicingPackages” /R /D Y

o    icacls <foldername> /grant Administrators:F /T in this case icacls “%WINDIR%ServicingPackages” /grant Administrators:F /T

b.     Overwrite all files in the destination folder if any are present.


7.     Perform Windows Update.





Optional Component Setup Log Diagnoser – http://technet.microsoft.com/en-us/library/cc732334(WS.10).aspx

Description of the System Update Readiness Tool for Windows Vista – http://support.microsoft.com/kb/947821

You cannot extract the contents of a Microsoft Update Standalone Package for Windows Vista – http://support.microsoft.com/kb/928636

Description of the Windows Update Stand-alone Installer (Wusa.exe) and of .msu files in Windows Vista and in Windows Server 2008 – http://support.microsoft.com/kb/934307

Command-line switches for Windows software update packages – http://support.microsoft.com/kb/262841

How to take ownership of a file or a folder in Windows XP – http://support.microsoft.com/kb/308421

Windows Update Agent – http://support.microsoft.com/kb/949104



2 responses

  1. David Hassmer

    Thanks! I tried to fix this error a thousand times, run repair-tools, update-preparation tools, net.framework-cleantools or what tool ever again and again – it did not work! But thanks to your description I got it solved finally! For a short term only I missed a hint, how to deal with missing rootpackages. But in the end everything is fine. All systems running. Great!

    March 22, 2013 at 6:42 AM

  2. Jason Stanley

    Thanks very much for the instructions. It fixed an issue installing KB2862335 that I had been messing with for several hours. Microsoft support articles didn’t help even though it was the exact same error but your fix did. Thank you.

    January 16, 2014 at 11:43 PM

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