Error Code 42B - Windows Update encountered an unknown error


This is only what I get every time I try to download updates for Windows Vista in my computer: "Error Code 42B" and Windows is unable to identify the cause !

The two updates I am unable to download are:
1) Office Live add-in 1.4
2) Microsoft SQL Server 2005 Express Edition Service Pack 3 (KB955706)

So, I would like to clarify the following :
A] The error Code 42B could be caused by a virus preventing me from downloading important features from Microsoft Update ?
B] Why Microsoft cannot identify the cause ? Would Vista not be that sophisticated ?
C] Would it be more than the two items above that Vista is not able to download or Vista is at least capable to tell me what it could not download?
D] How can I fix Vista to stop this failure from happening again?

Many thanks to whoever stops by and chimes in to help me out.

Question Info

Last updated March 25, 2018 Views 7,316 Applies to:

Hi Mentecapto-Elephantidae,

Thank you for posting your question.

Step 1: I would suggest you to try installing the updates by downloading the standalone package.

Download link:
Microsoft SQL Server 2005 Service Pack 3

Office Live Update 1.4

To install the updates from Safe Mode follow the steps as below:
Safe Mode disables most running processes and services. These services include the Windows Update service. Installing an update in Safe Mode is a quick test to verify whether an application or process is interfering with the installation.

a. Restart the computer. As the computer starts, press the F8 key.
b. Use the arrow keys to choose Safe Mode, and then press ENTER.
c. Install both the updates and restart the computer in normal mode.

If Step 1 fails, follow these steps:

Step 2: Check if the services related to Windows update are set to automatic and started.

Click Start, type services.msc in the start search box, right click services.msc and then click run as administrator.

Check the below mentioned services:
a) Background Intelligent Transfer Service
b) Cryptographic service
c) Windows Update

Step 3: Rename the Catroot2 folder

To rename the Catroot2 folder, follow these steps:

1. Click Start, type cmd in the Start Search box, right-click cmd.exe, and then click Run as administrator.
2. At the command prompt, type the following commands, and then press ENTER after each line:

net stop cryptsvc 
ren %systemroot%\System32\Catroot2 oldcatroot2 
net start cryptsvc 

3. Delete all tmp*.cat files from the following folder:


If no files that start with tmp exist in this folder, do not remove any other files. The .cat files in this folder are necessary for installing hotfixes and service packs.

Important: Do not rename the Catroot folder. The Catroot2 folder is automatically recreated by Windows, but the Catroot folder is not recreated if the Catroot folder is renamed.

Step 4: Reset Windows Update components

How do I reset Windows Update components?

Thanks and Regards,

Microsoft Answers Support Engineer

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