subscribe by email continues one email even after deletion

I had installed Subscribe by Email, and it seemed to work fine. However, I needed to disable it for a while, during some major uploading of posts from another WP site. Something has gone screwy, though -- I keep getting emails sent to multiple users, all for the same post, posted days ago. They just keep going out...

I do have AutoBlog also installed, and it works great. Are they somehow connected?

How do I get the Subscribe by Email stuff to STOP -- I would like to reinstall it later...