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Most email programs and services allow you to block, or at least divert, email from specific senders and domains. I'll look at a few techniques.

I have Windows XP. Is there some way to automatically refuse mail from some sites? I looked on the web but all I found was offers to download something -- some costly, some scary. It seems like I should be able to set something in Outlook that would block mail from certain addresses.

What matters here is not what operating system you run, but what email program you use, and in some case, what email provider you have.

The option to block by domain (meaning "from some sites") is not always available.

Since you mentioned you're running Outlook, I'll start there. Using Outlook 2007 as our example, click on Tools, Options, and in the Preferences tab, click on Junk Email.... In the resulting "Junk E-mail Options" dialog, click on the Blocked Senders tab, and then the Add... button:

Outlook, blocking a domain

You can see I've entered "". Press OK, and the list of blocked entries looks like this:

Outlook block list

Now any email that arrives which is from any address will be treated as junk. You can enter specific email addresses in this list, and/or domains, as I've done, which will block all email from that domain.

Now, it's important to realize that this occurs in your email program - Outlook - after the email has been downloaded. Chances are Outlook will simply move that incoming message directly to the junk mail folder once it's been downloaded if the sender is on the block list.

Other email programs may not support blocking users or domains directly, but you can simulate this using rules or filters. For example, in Thunderbird:

Rule to block email from a specific domain in Thunderbird

This filter causes all email from to be marked as Junk. Naturally you can create as many filters as you need.

In Outlook Express, this should work:

Filter to block email from a specific domain in Outlook Express

In all of the cases above, the email is downloaded, and then acted upon by your email program's filters. In order to prevent the email from even being downloaded you'll need to check with your email service provider - some provide server-side block lists.

Web based email services often also provide block lists. For example, in Windows Live Hotmail, you can click on the Options menu, More Options, and then under Junk e-mail click on Safe and blocked senders, and finally click on Blocked senders:

Blocking a domain in Hotmail

GMail apparently doesn't have a block feature, but much as we did above, we can set up a filter to automatically delete email from a domain:

Rule to delete all email from a specific domain

As you can see the tools available and the techniques you need to use vary greatly. You might be able to explicitly block a sender or a sender's domain, either in your email program, or on your server. If not, you might be able to use your email program or service's filtering capabilities to effectively block email from a specific domain or sender by simply deleting it.

But you'll need to investigate the options that you have and act accordingly.

Article C3699 - April 11, 2009 « »

Leo Leo A. Notenboom has been playing with computers since he was required to take a programming class in 1976. An 18 year career as a programmer at Microsoft soon followed. After "retiring" in 2001, Leo started Ask Leo! in 2003 as a place for answers to common computer and technical questions. More about Leo.

Not what you needed?

Peggy Skeen
April 14, 2009 9:00 AM

I have windowsxp, but under tools I do not have the options except Internet options. So how do I block unwanted email.

Colorado Pete
April 14, 2009 9:20 AM

I have been using a program named Mailwasher for several years. I began with the free version and went to the "Pro" version a few years ago. This tool works well as a pre-sorter of email. It has many features that will allow the user to block any unwanted email. is the supplier.

April 14, 2009 10:38 AM

How do I block url's - ie netflix, click*?

April 14, 2009 1:04 PM

I have XP and Outlook Express for mail...

I highlight the unwanted message,,then click on "message" up above, and choose "block sender"

I get a message telling me that "such and such" (the sender I wish to block)..will be blocked am I sure I wish to do this...I click yes, and they are gone...

and there are a list of all the senders I have blocked,,,in case I made mistake and had the wrong address highlight....

July 19, 2009 10:07 PM

I receive a lot of spam from various domains all ending in ".es" which is the country code for Spain.
Can I configure Hotmail to block all messages from ".es"?

robert smith
February 13, 2010 12:57 AM

i blocked e-mail by mistake but now want it back but the e-mail site was deleted, can it still be blocking my mail.

March 20, 2012 6:44 AM

Wow which was odd. I just wrote an very lengthy comment but soon after I clicked submit my comment didn't show up. Grrrr... effectively I'm not writing all that in excess of once again. Anyway, just needed to say superb blog!

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