What do you mean by "multi e-mails"?
Is it that some or all of the e-mails apears more than once in your in box?
It can appen if your e-mail server use the pop protocol and you tell it to keep downloaded messages. Change your settings to delete downloaded messages from the server.
Is it that you receive some unsolicited promotional/commercial e-mails, also known as spam?
In this case, there is not much you can do except deleting those. Use an e-mail client that have a spam filter to place them in a junk folder that you clean up from time to time. Thunderbird have an excelent adaptive spam filter.
Never EVER follow ANY link from that kind of message ! It's even more important that you ABSOLUTELY NEVER EVER buy anything from those!!!!! If you do, you'll only ends up receiving even more. Any "Remove me" link is realy a "You got a valid e-mail, and I'm a sucker! Send me more!" link.
If you buy something, anything, from those, you contribute to everyone in the whole world to receive ever more spam e-mails.
Finaly
Did you suscribe to any periodic e-mail? In some cases, it can be possible to suscribe more that once using slightly different informations for the same address.
In this case, you only need to follow the unsuscribe link that those normaly have.
Electro, August 2011