With the catch-all feature, email sent to misaddressed or misspelled addresses at your domain (for example, bob@ instead of robert@yourdomain.com) will be redirected to your free Yahoo! Mail account. To activate your catch-all:

Because the catch-all feature collects everything sent to your domain, it can accumulate spam. If you find you're receiving too much junk mail, return to the "Set Up Email Address" task and turn off your catch-all.