There are lots of emails floating out there trying to lead you to websites where they can steal information from you and in turn probably try to steal your money. On many email systems most of these messages end up in the junk or spam folder and most of you never see them.
My main email account is hosted on Yahoo by AT&T and in recent weeks I have received a number of emails claiming to be from one of those organizations and that I need to update my email account for a number of reasons. Reasons include that they are cleaning inactive accounts, wrong information in account, verifying security, etc. They say if action not taken immediately my account will be deleted or inactivated or in one case claimed legal action would be taken.
Usually these messages had logos for the correct company but there are several giveaways they are fraudulent. First this is March 2013 and they have 2012 or before copyright notices (one was 2006). Second is they just use my email address in the message and don’t know my name (however they are other messages sent where the spammers got address books or the names with email addresses on emails and send emails to you appearing to come from a friend with your actual name and usually just a link, don’t click that link). Third is looking at the address where it came from, usually it is some other domain than the organization claims to be from. Last hovering over the link in the message on a PC (does not work on mobile devices) shows where link goes to; then look at the very beginning and see the domain name (sometimes in the ling address they use they put names looking like http something near right end, but you want what is at very beginning on left) and see what it is. If the message claims it is from ATT and has an address that starts http://idiot.somewhereinuniverse.com then it is not really going to an ATT site.
Different email systems allow you to report these so they can try to stop them. Look at your host site for reporting fraud. For instance if it looks like it came from an ATT.net site you could report it to abuse@att.net
If you have opened one of these messages do not click on the links in the message and normally no harm has occurred. To make sure it did not plant something on your PC run a full scan with your anti-virus and anti-spyware software.