Users keep getting emails from them selves...

I administer a small network of about 100 users all with their own email addresses, and recently I have had a few calls from users who are getting spam emails from their own email address..  mainly stuff like, the usual..  sex, viagra, etc, etc..  I have already blocked as many phrases as I can to try and stop these mails getting through, but how do I stop mails coming from their own address...  either through sophos puremessage or even exchange 2003.   Baffled..  any help would be greatly appriciated..


Who is Participating?
millsclConnect With a Mentor Commented:
Postini could stop this.  It is a spammer trick to get by the filters.

Other third party products may work and be cheaper.  YMMV.
Jamie McKillopIT ManagerCommented:

This is a common spammer trick. You won't be able to prevent this with Exchange. You will need some type of third-party anti-spam software.

dazzzorAuthor Commented:
thanks jj
I use sophos anti-virus business console which comes with puremessage email filter..  do you know how I would do this..??

Alan HardistyCo-OwnerCommented:
Please read my EE Article for ways to prevent this without resorting to 3rd party software:
Alan HardistyConnect With a Mentor Co-OwnerCommented:
You don't need 3rd party software as long as you have Exchange 2003 Service Pack 2 installed, you just need to configure the built-in tools as per my article: 
All Courses

From novice to tech pro — start learning today.