AT&T's webmail system doesn't automatically deal with spam emails, which will come directly into your inbox if you don't set up a filter by activating Yahoo's SpamGuard in your Att.net account. SpamGuard may not deal with all of your spam emails, and you may need to adjust the system if it makes mistakes, but it will help you manage your spam messages.
Open your email account and log in. Click "Options" from the menu at the top of the page and select "Mail Options" from the drop-down list.
Click "Spam" on the Mail Options window. Check the box in front of "Automatically send suspected spam to my Spam folder" in the Control SpamGuard field in the Spam Options window.
Click the drop-down menu arrow in the "Empty Spam folder" field. Select a frequency option to set how often SpamGuard deletes your spam emails. Click "Save Changes" when you're done to enable SpamGuard.
If you have set up your Att.net email to come into a client email program, such as Outlook or Mac Mail, you can't access the Spam folder. If you want to check spam messages, you need to log into your account via webmail.
You may find that some emails go into your Spam folder by mistake. You can train the system to recognize these mistakes and to stop making them by marking messages as "Not Spam." This moves them back into your inbox.
Check your Spam folder periodically to see if it's filtering legitimate messages that should be in your inbox.
If you want to disable SpamGuard at any point, uncheck the box in front of "Automatically send suspected spam to my Spam folder" in the Spam Options menu.