Open you blog dashboard, that is where the compose button sits and all those buttons are on the left, along with the list of your posts, published and drafts. Go down to Settings and click, then Email. If you were receiving emails of blog comments, your email address will be there in the box next to 'Comment notification email'. Delete your email address within the the box and at the top right, click 'Save Settings'. It has been suggested that you should close down and restart your computer. Do so if you wish.
Then, go back to where you were at, Settings/Email and add your email address to the box 'Comment Notification Email' and again click Save Settings.You will receive an email and within the email there are two options. Select 'Subscribe'. Voila, you will now receive an email when someone comments on your blog. It may take a little time to start working though.
In my case it worked immediately !