We created Yahoo! AddressGuard so that when you are in the middle of buying something online, or signing up for something. You don't need to worry about giving your email address because you might get spam emails. You can protect yourself but not completely cut yourself off.
Yahoo! AddressGuard is part of Mail Plus. It lets you create disposable email addresses to use whenever you don't want to give out your real Yahoo! Mail address, but when you do think you'll probably want to receive what this source sends you—a receipt, or an invoice, or some other valid communication.
Yahoo! AddressGuard directs messages sent to these addresses into your Inbox so you can see them. You can also decide to direct them into one of your other folders if you want.
You can create many alternate addresses and access them all from your Yahoo! Mail Plus account. If any of your disposable addresses starts getting spam, just delete that address.
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