Helping people with computers... one answer at a time.

Sometimes updating your address book isn't enough to flush an old email address from your email program. We'll look at what else might be a factor.

I have a friend whose name and email address are in my address book. I sent items to him often, but I get mail administration returns saying the email did not go through because the email address was wrong and then it shows me his old email address.

His address changed months ago and I deleted it from my address book and installed his new email address and made it the preferred address.

What more can I do to get rid of this irritation?

The first thing that comes to mind is that your email program might be trying to be "helpful".

Too helpful, as it turns out.

My semi-educated guess is that it's auto-complete which is confusing things.

Auto-complete is that feature where as you begin typing an email name the program starts making suggestions on what email address you're most likely to be wanting. For example, all my wife has to do is type "L" in an address field in Outlook, and it automatically suggests my email address, so she just presses Enter and she's saved a lot of typing.

"The confusion comes from the fact that in many programs ... auto-complete suggestions don't come only from the address book."

The confusion comes from the fact that in many programs including Outlook, Outlook Express, Windows Live Mail, and I believe even Thunderbird and others, auto-complete suggestions don't come only from the address book. Most will include email addresses you've sent email to before regardless of whether they're in your address book. The result is that if you start typing a name and your mail program offers a suggestion it may still be the old address.

The next time pay careful attention to what it pops up as a suggestion. If it's the old address then in most programs you can hit down arrow to select it, and then hit Delete to remove it from the auto-complete list.

If you routinely use auto complete (as most of us do, it is pretty darned handy), you can test this theory by addressing the email by specifically using the address book. In most programs that's usually done by clicking on the "To:" button and selecting directly from the address book that pops up. That should get you the email address as actually stored therein.

Article C3285 - February 6, 2008 « »

Leo Leo A. Notenboom has been playing with computers since he was required to take a programming class in 1976. An 18 year career as a programmer at Microsoft soon followed. After "retiring" in 2001, Leo started Ask Leo! in 2003 as a place for answers to common computer and technical questions. More about Leo.

Not what you needed?

Nazrul Sheriff
February 9, 2008 8:18 AM

Many thanks - spent hours cleaning up the address books. I had Outlook as well as Windows Mail in Vista and sent me in a loop.
You were right as usual.
Kind regards,
Nazrul Sheriff.

Greg S
March 5, 2008 1:28 PM

Could be he needs to delete the nk2 file found in
C:\Documents and Settings\{username}\Application Data\Microsoft\Outlook

Comments on this entry are closed.

If you have a question, start by using the search box up at the top of the page - there's a very good chance that your question has already been answered on Ask Leo!.

If you don't find your answer, head out to to ask your question.