Windows 7 .net & windows installer corrupt?


New Member
Jan 27, 2013
Help! Please.

Not sure how much information to put, or how to lay it out, so I have done the best I can.
Sorry it is so long.

Other half's Toishiba SatellitePro has just broken itself!
Running Win 7 Pro 32 bit.
Not a new machine been running fine for a while now.
Hardware all seems OK.
It may be linked to the latest batch of MS updates, which won't install as 4 of them are .net.

It has fallen over or corrupted something in .net & / or windows installer.
However, as it seems that both the Windows installer & .net 4 are both "broken" and it also seems that they require each other for a fix?
i.e. .net4 requires Windows installer for a fix & vice versa?
I've just spent 2 hours searching on the internet for fixes, & have run the MS .net repair tool, which fails.
SFC/scannow also fails & chkdsk won't run as the volume is locked, both even in command prompt safe mode, and when chkdsk is set to run on next boot, it does not!
Don't have an install disk as it is a laptop which came pre-installed.

Trying to avoid a total restore to factory due to the time to rebuild the software on the machine, it runs our small business accounts, we do have an accounts backup & a backup of the documents folder.

It just seems that it is .net & installer that are affected.

When installing the latest round of MS updates:
Outlook update KB2768025 fails with error Code 91A Windows Update encountered and unknown error, and there is little other help available.
Tried a few "Microsoft FixIt" repairs for installer & .net they won't run as it seems they rely on each other?

The .net error that occurs is:
Unhandled exception has occurred in a component in your application. If you click Continue, the application will ignore this error and attempt to continue.
Could not load file or assembly 'Accessibility, Version=, Culture=neutral. PublicKey Token=b03f5f7f11d50a3a' or one of its dependencies. The given assembly name or codebase was invalid. (Exception from HRESULT: 0x80131407).

The machine is not used for programming at all, just for "office" type applications.

I have copied the text of the extended error message into the attached file.

Thanks for looking.
Please anyone, all help gratefully accepted!!!:confused:


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Someone else might recognize the entries in your attachment, but they are not familiar to me.

You can download and burn a copy of the Windows 7 SP1 .iso file from the following link. Maybe booting into the Windows RE from there would help. If not, failing other repair attempts you could reinstall Windows 7 over your current install which should allow you to keep your current setup. A good backup is always recommended. This of course assumes there is not a hard drive problem or any virus situations involved.

Edit: I suppose a reinstall might be effected by the fact you have an OEM install. Since I don't run one, I have no experience.

Official Windows 7 SP1 ISO from Digital River « My Digital Life

A System File Check can be run from offline, sometimes it will complete where the online one will not.

How to Run the System File Checker (Sfc.exe) Offline in Windows 7 and Vista - The Winhelponline Blog

I found one thread that said inserting the Office CD in the tray might help certain updates complete in case it is looking for some files. Others said to remove any blank media in the drive.

There is a log that might be helpful, if you can pick out error or failed entries around the time of the attempted Outlook update. It is the CBS.log and located in the Windows\Logs\CBS folder and must be copied to the desktop to open.

You might check the Services.msc panel and see if the Windows Modules Installer (TrustedInstaller) is running and if not can it be started. While you are there, you might as well try starting the Windows Installer to see what happens.

If it were to be necessary, the .net 4 client can be repaired or uninstalled from the Programs and Features panel.
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Thank you Saltgrass.
Part of the .net 4 system, the "Extended" section, will not repair from the add/remove programmes feature, this is one of my issues.
Have also tried the full downloaded installer package.
Have just created a repair disk, this time it worked!
Things are getting better, booted off that now running a chkdsk, which has found & is repairing errors.
I'll try the offline sfc thing next if the chkdsk does not work.
Thanks for the pointers.
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Managed to run chkdsk & fix "faults".
Also got SFC to run and got loads of errors in the cbs.log file.
Anyone able to advise please?
it seems like the "backup" versions of some of the files are also corrupt?
Is there any way to get "new" copies of these into the correct places without a re-install?
I'll try to upload a copy of the cbs.log shortly, but the one on the disk is too big to upload

Thanks for any help,
Yours desperately...


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There is another utility you might try. It seems to be able to repair things the SFC may not be able to, but basically it seems to repair the image used for your system.

DISM.exe can be run from an Administrative Command Prompt will hopefully rebuild your updates and some other things. The link is over on the Windows 8 Forums site. The online option means you need to be running the OS. If you were to boot into the Recovery Environment, you would probably have to use the offline options.

Sorry, it appears the commands given for Windows 8 are not useable in Windows 7, so the link is not really valid.

Hopefully it will help, and I will look at the log.

Edit: If you are running a Non-Microsoft anti-virus, there have been situations when it could interfere with certain activities on your system and cause problems.
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I had to remove the link since the commands do not seem to work in Windows 7.

Otherwise, it looks like your SFC did not finish, or you did not show the full log. It seems to mention Autochk.exe and Accessibility.dll, but the log appears to end around with approximately 50-60% of completion.
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If you were to decide to try to replace the files showing as bad in SFC, here are a couple of links. I have not done the procedure myself, so I won't be of much help. But you basically change the permissions on the bad file so you can delete or move it, and replace with the same file from a like install.

sfc /scannow detected some corrupt files.. unable to fix.. what to - Microsoft Community

Use the System File Checker tool to troubleshoot missing or corrupted system files on Windows Vista or on Windows 7
Thanks again for your help Saltgrass.

I generated the cbs.log file by, noting the time that I began the sfc tool, and then allowing it to run to completion, which it did not actually, but did seem to stop of its own accord part way through.

I then copied the original cbs.log & renamed it.
I then cut out all of the info prior to the start of the last SCF run.
So it does contain all of the data that was generated, but, IIRC the SFC tool did stop short.

Thanks again.
If the SFC doesn't finish, a file or files might still be unknown that needs repairing. I would try to repair the two files you know about and see if it helps.

The autochk.exe file is related to chkdsk so that might have a great deal to do with your problem.

My concern is, when SFC says the original and backup files are corrupt, I feel it is looking an another reference/s that disagrees with the files you have on your system. Since it checks Hashes, perhaps that reference if different for some reason.

This component was referenced by [l:198{99}]"Microsoft-Windows-Foundation-Package~31bf3856ad364e35~x86~~6.1.7601.17514.WindowsFoundationDelivery"

If you want to pull the SFC entries out of the log, just copy and paste this command in an administrative command prompt window.

findstr /C:"[SR]" %windir%\logs\cbs\cbs.log > %userprofile%\desktop\sfcdetails.txt

If the scan were to finish, the bad files would normally be listed in the last portion.
Thank you for your help Saltgrass, I appreciate it.

I got there in the end by doing an in-situ upgrade to the existing OS, I could get none of the tools to work, nor could I find the files that I needed to replace.

Thus, I bit the bullet downloaded & burnt one of the images you directed me to, & using the Product Key on the machine did an upgrade.
This seems to have worked, well at least, it installed & is allowing me to do updates.
It is currently updating .net Framework 4, so I should know shortly if all is well!

Thanks for the pointers, the big stumbling block for me was not having a "real" Windows 7 disk, which was overcome by the image link.
Thanks again.
Glad you got it worked out. I think I would keep a close eye on the system for any more signs of problems....
I spoke too soon!!!
Gutted, SFC now checks out OK.
Just going to scandisk the machine from a boot disk.
It keeps offering the same Windows updates, even though they list as OK.
1 is for IE10, I have hidden that as I have not tried to install it.
5 are for .net 4, sound familiar?...
They are KB-2487367, -2656351, -2468871, -2533523, -2600217.

KB-2670838, -2574819, -2592687, -2709981
& Bing desktop which I don't want & can hide, though I hid it once & it has come back!
I have not tried to install the optional updates at all.

I have tried KB2487367 on its own no joy.
The important updates ALL complete OK & show as a successful install, they just keep being shown again!
I've tried a few MSFixIt solutions none have worked.
I have cleared out the "C:\Windows\SoftwareDistribution\Download" folder with WindowsUpdate service stopped & rebooted, no joy.

Any further suggestions please?
Not sure if I should start a new thread?
This time the .net 4 packages already installed will repair OK.
I'm not sure if it is an installed .net 4 issue or a windows update issue now.
I once heard if you tell the system to check for updates, it might help clear up some offers to reinstall updates.

You did run the following command or the fix-it from the link?

Del "%ALLUSERSPROFILE%\Application Data\Microsoft\Network\Downloader\qmgr*.dat"

If you did not run it, go to the link and do the process following their instructions.

How do I reset Windows Update components?

When you get a chance, copy the WindowsUpdate.log from the Windows folder to your desktop. Copy the last 5 days or more of entries and paste into a notepad file, then zip and attach using the paperclip on the advanced replies.

I will look at it to see if anything might help.
I've done the manual "check for updates" bit, no joy! ;(

I've run several fixits!

chkdsk checks OK.

I'll run the command line command now from an elevated command prompt to see what happens.

I'll sort out the logs too.

Thanks again Saltgrass I really appreciate your help.
I have been comparing two of my systems.

The older system, installed using the original Windows 7 install DVD has the sections for .Net 4 Client and .Net 4 Extended. The new system, installed using a Windows 7 With SP1 DVD does not have the Extended section. (my 32 bit laptop also does not have the extended updates)

The old one has both the .Net 4 Client and Extended listing in Programs and features but the new one only has the Client listings.

In the View Installed Updates window, the old one seems to have the ability to uninstall the extended updates, to which all of the problem ones you list belong. All but one of those updates are listed in my basic .net 4 updates on the new system. The first one may be too old since this system was set up in October.

You said you could not uninstall the Extended .Net 4, was that because it is not listed or just will not uninstall. You might think about uninstalling the Extended updates to see what happens.

Just something to consider in your free time ... :)

Edit: Have you seen this site?
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I can now repair or uninstall the .net 4 apps.
So, I am now uninstalling the both of them!
Extended gone OK.
Now to remove the other .net 4 app.
Then MS updates...
Final update I hope.
Saltgrass, thank you VERY much for your support, your ideas, suggestions & links have been very informative & helpful.
When sat in front of a PC on your own, it is difficult to see the wood from the trees often.
I'm used to machine fault finding, but often have others to talk to about the faults, even if they have no idea about the fault, sometimes it helps to talk to anyone about the fault.
I uninstalled the both .net 4 versions.
Ran msupdate, & installed all the relevant updates required.
All seem to have gone on OK and, no more repeating updates!!!!!!!
Woo Hoo!!!

Thanks again, I'll keep a close eye on the machine & build the spare as soon as I can I think!

I really appreciate the help you have given & the time you have spent doing this.
If you ever need help with UK electrical works let me know! ;)
I even know a forum that helps... ;)
You are certainly welcome and I will keep your offer of help in mind...
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