There are a couple of reasons why Yahoo! Address AutoComplete might not work.

A few things to check:

• Is the address that you're typing in your Contacts folder? If not, Yahoo! Address AutoComplete won't work for you.
• Do you have the latest Yahoo! Toolbar? If not, Yahoo! Address AutoComplete might not work.
• Finally, you might have a compatibility issue with the browser you're using.

Supported Browsers:

• IE 5.5 and above for Windows and Mac
• Netscape 7.2 and above for Windows and Mac
• Mozilla 1.x and above for Windows and Mac
• Firefox 1.x for Windows

Remember, even if you can't autocomplete addresses, you can still insert contacts from your Contacts folder by clicking either "Insert addresses" or the "To:" link on your Compose page.