You can optimize the video and sound quality for your calls by using the "Yahoo! Video and Voice Setup" assistant to test and adjust settings for the calling equipment you'll be using on your computer. This setup assistant helps you check call sound quality for your microphone, speakers, and webcam.

Here's how to access the "Yahoo! Video and Voice Setup" assistant:

1. On the "Help" menu, select Set up Video and Voice. The "Yahoo! Video and Voice Setup" window will open.
2. Go through the three-step process to check your microphone, speakers, and webcam settings. Many laptops have built-in microphones, allowing you to look and speak directly into the computer.
   Note: If you don't have a webcam and just want to make voice calls, you can skip the webcam step.
3. When you're done checking your equipment settings, click Finish.

Tip: Run the "Yahoo! Video and Voice Setup" assistant any time you'd like to make sure your microphone, speakers, and webcam are working properly.

Important: Calls to 911 or other emergency calling services are not available on Yahoo! Messenger. Please inform anyone using your Yahoo! Messenger that they must call 911 or other emergency calling services with a regular telephone or mobile phone.