If I try to install the latest windows defender the verification works
OK but I get a message when I run the .msi file: "This installation
package could not be opened. Contact the application vendor to verify
that this is a valid Windows Installer package".

How can I fix this?

How to re-install Windows Installer:
http://xphelpandsupport.mvps.org/how..._windows_i.htm

Also:
Common Windows Installer Problems
http://support.microsoft.com/?kbid=555175

JS

"Robert S" <(E-Mail Removed)> wrote in message
news:(E-Mail Removed)...
> If I try to install the latest windows defender the verification works OK
> but I get a message when I run the .msi file: "This installation package
> could not be opened. Contact the application vendor to verify that this
> is a valid Windows Installer package".
>
> How can I fix this?

"Robert S" <(E-Mail Removed)> wrote in message
news:(E-Mail Removed)...
> If I try to install the latest windows defender the verification works OK
> but I get a message when I run the .msi file: "This installation package
> could not be opened. Contact the application vendor to verify that this
> is a valid Windows Installer package".
>
> How can I fix this?


I suggest you post to one of the Windows Defender newsgroups.

[From a post Courtesy MVP Malke]

- microsoft.private.security.spyware.announcements
- microsoft.private.security.spyware.appcompat
- microsoft.private.security.spyware.general
- microsoft.private.security.spyware.install
- microsoft.private.security.spyware.networking
- microsoft.private.security.spyware.signatures
- microsoft.private.security.spyware.onlinecommunity

These newsgroups can be accessed via NNTP or HTTP. To access these
newsgroups using HTTP, please go to the following location:
http://communities.microsoft.com/new...yware&sLCID=us

To access these newsgroups using NNTP, please use the following
information for your NNTP client (such as Microsoft Outlook Express):

- NNTP Server: privatenews.microsoft.com
- Account name: privatenews\spyware
- Password: spyware

NOTE: No password will be required via the HTTP link.