Is there a way I can stop spam from sending to myself, from myself?

I have noticed there has been a lot of spam mail coming from an account in our office and I just recently received an email from myself that was spam.  Is there a way to stop this?  I already have GFI Mail Essentials, which should be taking care of this, but I guess it isn't 100%.  Any ideas on what I could do to stop this?
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Implement SPF (or Sender ID) and add a SPF/SenderID record to your DNS. Then only email coming from your domain from approved IP addresses will be accepted. Any other forged email will be rejected.
SPF is not going to be the solution - if you implement it to drop anything incorrect, you will lose mail.

Configure GFI so that it drops incoming mail pretending to be from @yourdomain

As long as you don't have external users using POP3, you will be fine.

Michael WorshamStaff Infrastructure ArchitectCommented:
On the Exchange server, you can also setup an RBL check to keep the spam down as well.
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Jscott82305Author Commented:
How can I configure GFI to do this?
Add your domain to the blacklist; (page 71)

If GFI gets upset about that (which it might, last version I used was 10) you can do this from Exchange itself;

You want to block *

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Jscott82305Author Commented:
Thanks for your fast help!
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