| Getting Started | Working With the Spam Mail Folder | Training the Filter | Resetting the Filter |
We all hate spam. Spam, if you don’t know, is any message or posting, regardless of its content, that is sent to multiple recipients who haven’t specifically requested the message. Other common terms for spam include junk mail, UCE (unsolicited commercial email), and UBE (unsolicited bulk email). The most effective way to prevent spam from entering your Yahoo! Mail Inbox is to use SpamGuard. 
The SpamGuard tool uses filters that automatically send suspected spam to a special mail folder called Spam.

When SpamGuard is turned off, Yahoo! Mail delivers all incoming email, including spam, to your Inbox (and, if you’ve created your own filters, to other folders). When it’s turned on, SpamGuard identifies suspect messages and routes them to your Spam folder, where you can review them.
If you’re a Yahoo! Mail Plus user, you automatically have access to the SpamGuard Plus tool. SpamGuard Plus enhances basic SpamGuard functionality by using your own personal spam filter, in addition to the general SpamGuard filter. By marking messages as Spam or Not Spam, you develop a training history for your personal spam filter.
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In the upper-right corner of your Yahoo! Mail page, click the Options link, then select Mail Options from the menu.

The Mail Options page opens.
Under the Spam column, click the Spam Protection link.
Tip: The first time you open Spam Protection, Yahoo! Mail takes you through a series of steps to set up your spam options. Afterwards, the Spam Protection page shows your initial setup options. The following steps describe this page and how to change your options.
In the Spam Filter section of the Spam Protection page, you should see that SpamGuard is on.
If SpamGuard is off, click the Turn SpamGuard ON link to turn it on.

Choose one of the following options to specify what SpamGuard should do with spam messages:
Immediately delete these messages upon receipt.
Tip: Sometimes, based on the information it uses for filtering messages, SpamGuard may classify a valid email message as spam and deliver it to the Spam folder. If you select the "delete immediately" option, you won’t have a chance to review the messages in your Spam folder before Yahoo! Mail deletes them.
Save these messages in the Bulk Folder for:
Select a period of time from the pull-down list:

Note: The Bulk folder is an older name for the Spam folder.
Click the Save Changes button.
SpamGuard becomes even more effective as you use it because you train it to recognize what you consider to be junk mail.