Well, I’m done. Good luck
Thanks for your help anyway
I will explain once more, you need to change the settings on your phone to disallow installation of apps from unknown sources. It will then download Manager msi file without trying to launch it.As you seemed to have done before you can then transfer the file to the PC.
@Joe91 gave you good advice also by downloading directly onto your PC using the phone as an internet access point for the PC.
Any security alert on installation on PC itself is normal and you should follow the OS guideline to clear the warning.
Hello everyone… I managed to download Manager today successfully… I can’t wait to see wat the developers got for me… Cheers everyone 
that offered advice… Thanks