Click on the offending email.
Click on the More box, on the right, just under the Google search box.
- Click on “Filter messages like these” (one before the bottom of the list)
- Click on “Create filter from this search”, (bottom right). If it is a company and you don't want messages from anyone there, go to the From field at the top of the page, and remove the left hand part of the email address up to the @ sign.
- Click on “Delete it” (the 6th box down.
- If you want to delete all emails on your computer from this exercise, click on “Also apply filter to ? matching conversations”. (? will be the number of messages in Gmail).
- Now click on the blue box stating “Creat Filter”.
Please remove me from your mailing list.
You may elect to ignore my request. However, I use an email program which allows me to delete all emails from a specific address (or domain) sight unseen. So your emails would disappear for ever if you choose to go down this route.
Also, there may be other consequences. I may want to deal with you in the future. But I would never see your reply and may end up dealing with a competitor.