If your business doesn't currently have an mail filter at the server end, you are likely being inundated with a number of unwanted emails that you're unable to unsubscribe from. Commonly known as spam, this unwanted email will attempt to seduce you into undertaking some action to enrich their lives.
If you use Outlook you can block some automatically by using the Junk email option on the toolbar, here's the steps to automatically set block one incoming email address :-
- Choose the Home tab, and highlight the email in question
- Click on the Junk option in the Ribbon, and then Block Sender
- You'll be asked to confirm that you want to block the sender