Even though they may say so, these "reminders" do not come from Microsoft.
They are a hoax, and they could contain a virus as an attachment. Delete
them immediately without opening the attachment.
One way that may help minimize the number of these messages is to create a
message rule that deletes from the server any incoming email that does not
have your real email address in the TO or CC line.
However, you invite spam mail because you are using your real email address
in your newsgroup posts. Use a fake address instead.