From your description of this message, I would suspect a corrupted download,
and would suggest downloading again, saving to the desktop, and
double-clicking the file on the desktop.
If you again get this message via that procedure, post back to this thread
and ideally copy the message completely, so we can research it better.
--
"Karen" <(E-Mail Removed)> wrote in message
news

54938BC-35BB-4E06-89A1-(E-Mail Removed)...
>I have downloaded Windows Defender (Beta 2) to my desktop. When it tries
>to
> install, a message comes up saying it is an unknown publisher and to
> contact
> the product vendor. Is there anything I can do to get it to run?