Envoi de spam

Bonjour,

bonjour,

je pense que mon adresse mail est utilisée pour envoyer des spam. je viens de recevoir ce message

This is an automatically generated Delivery Status Notification.

<ital>Delivery to the following recipients failed.

xxx@hotmail.com
xxx@hotmail.com </ital>

concernant ce message

Dear ,
This must be a good surprise for u to purchase online,brand new and original electrnics.U can have a look.
If you in large orders ,we can offer you some discount,and offer you a small gift ,it must be a joy and surprise for you.
If over 500USD,free shipping
If over 1500USD,a gift Apple Nano 8GB and free shipping(except motorbikes)
If over 2500USD.A gift :Apple Iphone 3GS 16GB and free shipping(except motorbikes)
If over 5000USD,10% discount,and free shipping(except motorbikes)
(www.beiwei-shop.com)
2010116wb

que je n'ai jamais envoyé. QUe dois je faire? Changer le mot de passe de mon mail? Un nettoyage du pc s'impose surement.... Merci de m'aider.