Gmail Filters and Blocked Addresses

We will guide you make use of Gmail filtering feature to block emails from email addresses you don't want to receive email:

Login to your Gmail account and select the email message you want to block by clicking on the square on its left side. Check out Gmail Sign In tutorial.
Click on the "More" option at the top of the email messages list. On the drop down menu that appears, click on "Filter messages like these”.
On the new dialogue box, click on the "Create filter with this search >>" at the bottom right of the box.
You'll then be provided with several options. To completely block an email address, click on the checkbox on the left of "Delete it" option.
If you also want to delete all the previous conversations with the email address, click on the checkbox on the left of "Also apply filter to [Number of conversations] matching conversations." Option.
Click on the "Create filter" button at the bottom left of the box to ensure that the email address is completely blocked. You're done. If you've got any messages from that email address in any of your Gmail folders, they'll be deleted. If you later want to receive email messages from that address again, you can undo this process.