#1 Rule of a clean inbox is
Only give real people your primary email address. Create a junk email account with Gmail to catch all the junk. You'll still be able to retrieve the confirmation emails you need to gain access to websites, without permitting overzealous salesmen to flood your inbox.
Teach your PC what "junk" is
Make use of your email client's Junk Folder System. Most web based and program based email clients send emails it thinks are junk into a special folder called the Junk Folder. Most email clients also learn what is junk and what is not junk based on what you tell it. Learn how to use your email client's Junk Email System, and you'll be well on your way to a spam free Inbox.

Filtering & Antivirus
If your Junk Email System is not enough; you have options such as Google's Postini for small and medium business. Run all of your emails through Google's Postini Email Filtering Service, and you'll get the same email filtering power as Gmail. Google has other options like email antivirus and email archiving as well. Individuals can use Google's filtering service too, starting at just $12 per year!

In house solutions
While Google has an impressive email filtering service, some business owners prefer to have their filtering done in house. This is when Barracuda Networks comes into play. When leading organizations need to safeguard email, they most often turn to the world’s #1 selling email security solution—the Barracuda Spam & Virus Firewall.
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