You could try this.
Go to Control Panel (Classic View) > Windows Update. Click on Change
Settings. Choose "Never check for updates (not recommended)". Un-check the
box under "Recommended updates". Click on Okay. Close Windows Update.
Go to Control Panel (Classic View) > Windows Firewall. Click on Change
Settings. Choose "Off (not recommended)". (Apply, OK). Close Windows
Firewall.
Try starting Windows Defender (Start Menu\Programs). If it starts, click on
the down-arrow to the right of the Help icon, and choose "Check for
updates". Let Defender check and download the update.
If Defender does not open, or if it opens, but doesn't download the update,
go to
http://www.microsoft.com/security/portal/
Under "Latest Definition Updates", choose your operating system type, 32-bit
or 64-bit, and try the manual download. Note here the instructions
pertinent to Vista:
http://www.microsoft.com/security/portal/ADL.aspx#top
Hoping this works, but either way, re-enable Windows Firewall and put your
Windows Update settings back the way they were.
"Mano" <Mano@discussions.microsoft.com> wrote in message
news:9031E47D-07AE-4924-869A-74FBC65BE4EF@microsoft.com...
> hi nevet, I am having the same problems and was wondering if you figure
> out
> the solution. i have try all the suggestion with no luck.
>
> "dean-dean" wrote:
>
>> Hi Nevet. You might try this. Go to the main Windows Update window and
>> click on "Installed Updates" (on the left-hand side of the window, at the
>> bottom), and then remove "Update for Microsoft Windows (KB931099)"
>> (only).
>> Reboot. Reboot again. Go back to Windows Update, and re-install the same
>> update, by clicking on the Check for Updates button.
>>
>> This should essentially re-install Windows Defender on Vista.
>>
>>
>> "Nevet" <Nevet@discussions.microsoft.com> wrote in message
>> news:41903B05-21DC-479F-8C51-2250FE3BDF06@microsoft.com...
>> > Thanks, Engel! This looked right, but doesn’t seem to apply to Vista.
>> > Running appwiz.cpl, Windows Defender doesn't even show up on the list
>> > of
>> > installed Program and Features, nor under Windows features to turn on
>> > or
>> > off.
>> > It is also not listed in the Windows Installer CleanUp utility
>> > (http://support.microsoft.com/kb/290301/). And when I try to reinstall
>> > from
>> > http://www.microsoft.com/athome/secu...yware/software, as the KB
>> > article
>> > instructs, I get the message “You do not need to install this software
>> > because Windows Defender is included in Windows Vista. You can access
>> > Windows Defender from the Security section of the Windows Control
>> > Panel.”
>> >
>> > Windows Security Center shows (under “Malware protection”) that Windows
>> > Defender is turned off. “Turn on now” churns for a while, then says,
>> > “Security Center can’t turn on Windows Defender. Please try again
>> > later.”
>> >
>> > Any other ideas?
>> >
>> >
>> > "Engel" wrote:
>> >
>> >> Hello Nevet,
>> >>
>> >> Error message when you run Windows Defender: "Error Code 0x800106ba
>> >>
>> >> Try this
>> >> http://support.microsoft.com/?kbid=931849
>> >>
>> >>
>> >> I hope this post is helpful.
>> >>
>> >> Let us know how it works ºut.
>> >>
>> >> --
>> >>
>> >>
>> >>
>> >> "Nevet" wrote:
>> >>
>> >> > Running Vista Home Premium. When starting the OS, I get an error
>> >> > message
>> >> > from Windows Defender:
>> >> >
>> >> > "Application failed to initialize: 0x800106ba. A problem caused
>> >> > Windows
>> >> > Defender service to stop. To start the service, restart your
>> >> > computer
>> >> > or
>> >> > search
>> >> > Help and Support on how to start the service manually."
>> >> >
>> >> > Attempting to manually start the service brought up another error:
>> >> >
>> >> > "Windows could not start the Windows Defender service on Local
>> >> > Computer.
>> >> > Error 0x80092003: An error occurred while reading or writing to a
>> >> > file."
>> >> >
>> >> > I have uninstalled my third-party (McAfee) security suite so
>> >> > Defender
>> >> > is all
>> >> > I have on this machine.
>> >> >
>> >> > I found similar reports on various newsgroups but no solution,
>> >> > workaround or
>> >> > fix offered.
>> >> >
>> >> > Any suggestions?
>> >> >
>> >> > --Nevet
>>
>>