How to Find an Old Email Address
Old email addresses are the ones that your contacts don't use anymore. If you have lost touch with someone and want to find his or her old email address, or if you just want to send a message to an old email address for fun, there are lots of ways to find them. Some ways might work for you, while others don't. But keep trying, because finding old email addresses is usually a task that you can complete quickly.
Look through folders in your in-box to see if you've saved some old messages from the person you'd like to find an old email address for. If you've saved some old messages, you might find the person's old email addresses. Also check forwarded messages that you've saved, even those that others have sent. If someone else only has an old email address for your friend, it might be on the list of recipients a forwarded message was sent to.
Search through your own Sent folder, and go back as far as possible. The emails you sent to the person a long time ago might have an old email address on it.
Search online for something that corresponds with the time frame of the old email address. For instance, if your friend had the email address while in high school, see if you can find an old list of high school students your friend might be on. If the email address is from a time where one of your relatives played soccer, see if you can find an old listing for the soccer team. Old contact information, including email addresses, may still exist at some sites, especially those that haven't been updated in a while.
Go through your old offline address books and correspondence. Often, when email addresses were new, people would write them down and give them to someone. It could be that the one you are looking is one you've written down and perhaps forgotten about.