Normally when I send/receive email, the sender/receiver address is mine - PRIVATE INFO REMOVED. Now, the address is - "Tobacco Award Promo". Looks like my email address has been hijacked.
This is a copy of the result of sending myself a message.

Hijacked email addressTuesday, December 22, 2009 10:56 AMFrom: This sender is DomainKeys verified"Tobacco Award Promo" <PRIVATE INFO REMOVED>View contact detailsTo: "PRIVATE INFO REMOVED" <PRIVATE INFO REMOVED>

Any recommendations to clear up this mess?
I may also add that my Avira AV connection has been shut down.

Help will be appreciated.

Scan your system with MalwareBytes (the free version blue button in the link)

Malwarebytes.org

If Avira still doesn't work, uninstall it and reinstall it.

It's possible that you have an infection on your computer that's messing up your e-mail.

Save your data and fight the worm.