Link for Windows download is broken
https://storage.googleapis.com/kubernetes-helm/helm-v2.8.0-rc.1-windows-amd64.zip
Proper link is https://storage.googleapis.com/kubernetes-helm/helm-v2.8.0-rc.1-windows-amd64.tar.gz (tarball as opposed to a zip). Would you mind letting us know where you found the link so we can update it?
Ah nvm I noticed it was on the release page. I've updated the link now.
cc @adamreese
Just an FYI this was fixed in master via #3274 so v2.8.0 windows builds will be available via zip again.