what do you do when someone uses your yahoo domain name e-mail address as spam?

Question

I have a yahoo personal website and recently I have had this stuff come into my mail box and I have not sent any mail from this address in a long while. They have my domain name at the end of their e-mails and no one else has access to my e-mails but me and I have not given anyone an address to use on my account too.
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Postmaster@ aedvoerg.de

What I need to know is how can I stop others from using my domain name in their e-mails?
Is there a way I can turn off my web domain e-mail address without losing my site?

Thanks for the advice. I am gonna change my password again. There are no e-mail address on my account that I did not make. But I will change my password anyways. Also I have places my domain name in my block area and since then I have not received anymore. I hope this fixes it permanently.But I think it is the second answer. That one seems to fit the most. Thanks again

Answer 1

If they are just spoofing your domain name (using it as the "from" address without actually sending mail through the servers) there isn't much you can do. You could contact the ISP whose mail servers sent the spam, because that sort of thing has to be prevented at their end.

Many e-mail worms exploit this- when they infect a computer, they collect all the e-mail addresses from the Outlook/Outlook Express address book and randomly pick one for each outbound spam message.

From wikipedia:

Note that the "To" field in the header is not necessarily related to the addresses to which the message is delivered. The actual delivery list is supplied in the SMTP protocol, not extracted from the header content. The "To" field is similar to the greeting at the top of a conventional letter which is delivered according to the address on the outer envelope. Also note that the "From" field does not have to be the real sender of the e-mail message. It is very easy to fake the "From" field and let a message seem to be from any mail address. It is possible to digitally sign e-mail, which is much harder to fake. Some Internet service providers do not relay e-mail claiming to come from a domain not hosted by them, but very few (if any) check to make sure that the person or even e-mail address named in the "From" field is the one associated with the connection. Some Internet service providers apply e-mail authentication systems to e-mail being sent through their MTA to allow other MTAs to detect forged spam that might apparently appear to be from them.

Other common header fields include (see RFC 4021 or RFC 2076 for more):

Answer 2

Ok, you have a security issue. Go into your yahoo! geocities account, and make sure no emails exist, except for the ones that you created. Make sure there are no viruses on your computer to get your passwords, etc. Change your yahoo! passwords, to complex ones. (good password: AeT2o03tEr)
Use capital letters, and lowercase letters, and numbers too.