646 Windows encountered an unknown error

decann

New Member
Dell Inspiron 1720 laptop
Vista Home Premium, SP2
Intel Core 2 Duo CPU T7250 @ 2.00GHz 2.00 GHz
3 GB of RAM
32-bit operating system

Above is all of the pertinant system information on my daughter's new (1 year or so) laptop, which very recently stopped accepting Microsoft updates, giving an error saying "646 Windows encountered an unknown error" which tells me nothing at all, nor how to resolve the issue. I have a written list of current updates if is pertinant information, but no matter which one I try to update I still get the same error so it apparently is all of them. . .including future ones since another one came in since discovery of the error and was not allowed to install either.

Can ANYONE out there help me resolve this issue, please? I am about to begin searching online for something to help resolve this issue, but I have never been very good at doing that and would welcome any guidance or advice IN BABY STEPS with step-by-step directions, PLEASE. System information is above, and I will furnish other information if requested.

On a side but related note, some of you may recall me from a month or two with a similar problem in my own laptop, a Dell Inspiron 1525. There, I was trying to update to Vista SP2 and got a different error, which never did get resolved despite going through Microsoft as well as Dell Tech Support multiple times. In the end, MS had me clean off the hard drive to fix it, and reinstall Vista requiring Dell to finally clean up "some loose ends" enabling me to finally properly reinstall everything, EXCEPT SP2, which will remain uninstalled.

I mention this here ONLY because my daughter's laptop has far too much in it for total reinstallation of software to be an option. It operates fine in all ways OTHER THAN the fact it suddenly will not allow the updating of MS updates, and that worries me. I would be very grateful if someone out there can offer some guidance or suggestions to a user who have reason to be VERY nervous doing stuff like this in the inner workings of a computer. :confused:
 

My Computer

Dell Inspiron 1720 laptop
Vista Home Premium, SP2
Intel Core 2 Duo CPU T7250 @ 2.00GHz 2.00 GHz
3 GB of RAM
32-bit operating system

Above is all of the pertinant system information on my daughter's new (1 year or so) laptop, which very recently stopped accepting Microsoft updates, giving an error saying "646 Windows encountered an unknown error" which tells me nothing at all, nor how to resolve the issue. I have a written list of current updates if is pertinant information, but no matter which one I try to update I still get the same error so it apparently is all of them. . .including future ones since another one came in since discovery of the error and was not allowed to install either.

Can ANYONE out there help me resolve this issue, please? I am about to begin searching online for something to help resolve this issue, but I have never been very good at doing that and would welcome any guidance or advice IN BABY STEPS with step-by-step directions, PLEASE. System information is above, and I will furnish other information if requested.

1.Uninstall all 3p security software firewall,antivirus,antispyware
2.Run cmd.exe with administrative previlliges and type:

netsh winhttp reset proxy

+restart

3.If above solutions don't help turn off Windows Firewall too.

On a side but related note, some of you may recall me from a month or two with a similar problem in my own laptop, a Dell Inspiron 1525. There, I was trying to update to Vista SP2 and got a different error, which never did get resolved despite going through Microsoft as well as Dell Tech Support multiple times. In the end, MS had me clean off the hard drive to fix it, and reinstall Vista requiring Dell to finally clean up "some loose ends" enabling me to finally properly reinstall everything, EXCEPT SP2, which will remain uninstalled.
1.Try reset WU componnets in aggressive mode How do I reset Windows Update components?
2.Delete all *.xml files from C:\Windows\WinSxS folder
3.Uninstall all 3p security software -firewall,antivirus,antispyware
4.Try install SP2 standalone version (not from Windows Update) in safe mode

If above steps don't help folllow below

1.Run cmd.exe with administrative previlliges (right click on cmd.exe as admin) and type:

sfc /scannow

2.Run Readiness Tool http://www.microsoft.com/downloads/...06-c27d-4483-bc1f-04d43fa7b293&displaylang=en
3.again run cmd.exe and type:

cd /d C:\Windows\inf
dir /s /b >%userprofile%\Desktop\Inf.txt

above commands create Inf.txt log on your desktop.

4.Pack all following files:

C:\Users\<your account>\Desktop\Inf.txt
C:\Windows\logs\cbs\*.*
C:\Windows\WindowsUpdate*.log
C:\Windows\inf\setupapi.dev.log
C:\Windows\winsxs\poqexec.log
(if exists)
C:\Windows\winsxs\pending.* (if exists)
C:\Windows\Performance\WinSAT\Datastore\*.*
C:\Windows\System32\winevt\Logs\application.evtx

and upload them to RapidShare: 1-CLICK Web hosting - Easy Filehosting

5.Download VistaSysInfoTool VistaForums SysInfo Tool ,select all in this tool and generate log.Log attache to post or upload with other required files on rapidshare
 
Last edited:

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Flavius, thank you for the reply, nut did you send the CORRECT instructions? For one thing, please note that the top of my original post states this is a 32-BIT system in Vista, and yet all reference in your directions state 64-bit. Do I have correct directions?

Also, what do you mean by "Uninstall all 3p security software firewall,antivirus,antispyware?" WHAT IS "3p security" software? I use McAfee Total Protection, but is that what you mean? Does it HAVE TO BE REMOVED, or can it simply be shut off using the built-in settings for that purpose?
 

My Computer

Flavius, thank you for the reply, nut did you send the CORRECT instructions? For one thing, please note that the top of my original post states this is a 32-BIT system in Vista, and yet all reference in your directions state 64-bit. Do I have correct directions?
Yes.You have right -it was my mistake.Of course you have to use 32bit Readiness Tool Download details: System Update Readiness Tool (KB947821) [September 2009]
I corrected my previous post too.

Also, what do you mean by "Uninstall all 3p security software firewall,antivirus,antispyware?" WHAT IS "3p security" software? I use McAfee Total Protection, but is that what you mean? Does it HAVE TO BE REMOVED, or can it simply be shut off using the built-in settings for that purpose?
Yes I mean firewall,antivirus,antispyware (here McAfee)-first you can try only shut off,if still no results remove McAfee completely.
 

My Computer

Flavius, thank you for the reply, nut did you send the CORRECT instructions? For one thing, please note that the top of my original post states this is a 32-BIT system in Vista, and yet all reference in your directions state 64-bit. Do I have correct directions?
Yes.You have right -it was my mistake.Of course you have to use 32bit Readiness Tool Download details: System Update Readiness Tool (KB947821) [September 2009]
I corrected my previous post too.

Also, what do you mean by "Uninstall all 3p security software firewall,antivirus,antispyware?" WHAT IS "3p security" software? I use McAfee Total Protection, but is that what you mean? Does it HAVE TO BE REMOVED, or can it simply be shut off using the built-in settings for that purpose?
Yes I mean firewall,antivirus,antispyware (here McAfee)-first you can try only shut off,if still no results remove McAfee completely.


Flavius (or anyone else who can help) -- I have followed your directions to the letter, and still have the same problem and MS Updates still piling up and uninstalled:

1. Totally removed all AV software (McAfee Total Protection)

2. Run cmd.exe with administrative privileges then enter “netsh winhttp reset proxy”

3. Tried UNsuccessfully to run Microsoft Update again.

4. Reinstalled all McAfee software

5. It was not clear from your directions whether I was to try to update with McAfee gone or installed, so I tried it again at this point but again with McAfee reinstalled and all updates failed.

What is going on? Do you know if there is anything that I can do to rectify this problem? I have three other computers, including one other laptop, all running on Vista but none of the others have experienced this problem.

Please help me. I am currently "hiding" the MS Updates as they come in, since they will not install, but the security and other updates need to be installed.
 

My Computer

Hi guys finally I found a solution for this error 646 ,just disconnect the network after downloading while the windows is installing if didn’t work just restart the computer and don’t connect to the internet ,go back to the windows update and press install ,because they will be already downloaded ,and it will work (vista SP2)
 

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