To make sure Yahoo! Mail works properly in your web browser, you may need to clear the browser's cookies and cache occasionally.
The cache (pronounced CASH) is the memory your browser uses to temporarily store the files that are automatically requested by visiting a web site. Storing those files lets your browser more quickly reload pages from the cache rather than transferring information across the Web over and over. This can save you time, and saves the network the burden of some additional traffic.
Your browser's cache is located on your computer's hard drive, and therefore it is a good routine maintenance to clear your browser's cache from time to time.
Clearing the cache may resolve issues such as: Browser never finishes loading page, page hangs, or freezes, seeing old page content, online applications not responding.
Cookies are small pieces of information stored on your computer by your browser to customize what you see on a webpage. It is usually good troubleshooting to delete cookies when you clear the cache.
Clearing cookies may resolve issues such as: Sign-in problems, not being able to stay signed-in, error messages about setting your user cookieHow to clear your browser's cookies and cache