The simplest solution would be for someone to retag one question with onedrive then we can merge the tags.
This will have the effect of retagging the rest of the questions tagged skydrive and automatically convert "skydrive" to "onedrive" when anyone uses it on a new question.
This has now been done.
If it happens again:
Go to one of these users profile, then to one of their posts.
Flag the post, use it needs ♦ moderator attention/other, and explain what you think is going on.
This is better than public shaming. You might be wrong, and this case it would be very unfair to expose the user in a public post.