HELP! can receive email, but cant send--possible virus?

Posted on 2006-04-27
Last Modified: 2010-04-11
Wednesday we started receiving these emails we never received beofre from different addresses with the same content about some business opportunity. everyone in our company received them. Now today we can receive email, but we cant send to certain of our big customers (who I know have very good security). We can recieve from them but we cant send. Our emials come back and say "Body of message generated response: 550 5.7.1 reject: message blocked" I think we may have goten a virus that was sending emails out, but I dont know what to do. Our antivirus software hasnt reported anything, and I am ata loss. Can anyone help?
Question by:kevotron

    Expert Comment

    hello ,
    try to send mails to another destination to check if they're blocked by your ISP or your customer ?

    Author Comment

    OK I found out what it is. We have a virus and it was sending out spam and we got blacklisted.
    LVL 2

    Accepted Solution

    Make sure that you have reverse dns configured for your domain or you'll have trouble with AOL recipients in the future.

    Also, make sure that your server is not an open relay or you'll get blacklisted again!

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