That domain can't be added to the blocked senders list.

[HelpRa]

I receive tons of junk email. I was blocking the domains and for some reason Microsoft will not allow me to block @live.com.uk. It says, That domain can't be added to the blocked senders list. I'm assuming this junk email has a Microsoft domain so it's impossible to block these daily junk emails.
Help
Thanks,
RW