Windows Defender Installation Problems!!HELLPPP

HELPPPP!!!, :banghead

I hope someone out there can be able to help me. I have tried to install the latest version of windows defender as the old one has become obselete and will not open at all because it has expired but microsoft cannot be bothered to tell you that in plain english, instead your greeted with an error message everytime you switch on the pc unless you unistall the program.

Anyway my problem is that i have tried installing the lastest version from microsoft website file name "windowsdefender .msi", it downloads fine but when i try to run or initialize installation, it wont let me, instead it comes up with a box that says windows cannot open this file: To open this file, Windows needs to know what program created it...Then it offers you the option to select the program manually or for Windows to go online to look it up automatically"

I do not have the program to select manually and Windows cant seem to find it either. Can anyone help please???

Thanks Tony.

 

ISSUED SOLVED!!!

Am posting this for anyone else who experiences the same problem.

This is how i did it....

1) Place windowsdefender.msi on the desktop:
----
OK--here's another way: You have "windowsdefender.msi" sitting on the
desktop, right?

Do Start, Run, and cut and paste the line below into that box marked Open,
and hit OK:

msiexec /i "%userprofile%\desktop\windowsdefender.msi"

Be sure to get both quote marks in there.

I do not know why this happened but i think it had something to do with the windowd installer not working correctly.

Tony.