that does not sound like a virus.

That is a message from the server that email address cannot be located - depending upon the actual message.

Sounds like either you sent a load of emails to email addresses that are not valid or live

OR Someone is abusing your email address and just spamming a load of email addresses in the hope that it gets through. You would not have known about it unless you got a mailer-daemon message. Your contacts may have received weird emails thinkng it was from you. Delete the messages. Tell your contacts about the abuse and tell them to never reply to such emails. Use a signature on your emails and tell contacts that a genuine email from you will have the signature.

Eventually, the abuser gets no response and gives up.

if it is a spam, how can I get rid of it? I receive a message on every 2-3 sec. I did not send messages to emails that are not valid. Should I contact the internet provider maybe they can fix this issue?

http://en.wikipedia.org/wiki/Backscatter_(email)

You can probably create a filter until it stops. http://kb.mozillazine.org/Filters_(Thunderbird)

I changed my email account and the issue is gone.

Thank you