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I'm very paranoid. Don't ask why because that's besides the point here.

I want to create a domain with some random name, such as

And then, when anyone asks for my email address, I want to generate a new random email forwarder for that person to use, such as

I think this is perfectly legitimate approach, because if I have tons of email forwarders, and I notice spam coming through one of them, I can just shut down that forwarder. It also contributes to my feeling of privacy online, so it's important to me.

But my question is: If I set up my mail servers up like this, will I get into trouble getting through other people's spam box filters when sending and replying to emails? Is that how spam filters work?

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You should look at, who automate this process for you. (I used them back when they were unpaid and the service worked great.) – Shinrai Jun 21 '11 at 14:18
Similar to what did previously too. – Macke Jun 21 '11 at 14:59
:) I'd pick a good domain name, but other then that. That is a great idea! – William Jun 21 '11 at 21:50
Please note that you it's impractical to generate a new random forwarder when you are out and that the e-mails are pretty hard to remember for people. So, aren't you better off with a ticketing system that has a ReCAPTCHA instead of going through all this unnecessary hassle? If you create more addresses you increase the chance of getting more SPAM that you would get with a single address... – Tom Wijsman Jun 21 '11 at 23:52
Is this like what Bouncr does? – Marcel Jun 22 '11 at 0:33
up vote 18 down vote accepted

Potentially, but then no more than anyone with a regular domain name.

Spam filters look at the contents of e-mails to determine whether they might be spam or not and if you trust a sender you add their e-mail (either the specific address or the entire domain) to your whitelist.

Now, while your domain and address is random, it should be treated no differently to "normal" ones.

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Make sure you have all the reverse DNS entries set up though, or almost all of your email will be blocked. – Darth Android Jun 21 '11 at 14:08
Thanks, I'll allow some more people to comment and then choose the best answer. Voted yours up. Thanks! – Enchilada Jun 21 '11 at 14:10

I actually do exactly that on my Exchange Server: I create different e-mail addresses for every business I do business with, and associate them all with my account. I have Dell@, Symantec@, etc. If one starts getting SPAM, I can delete it, but I also know who is not careful with my e-mail address.

You will potentially run into problems, but not because of the domain name. How do you plan on sending the mail? The main issue that I can see facing you is the PTR record: Many domains, and most of the large ones, will drop your mail as SPAM if you do not have a PTR DNS record.

If you do not have a business class Internet connection with a static IP, you will not be able to get this (you have to ask your ISP to do it too), but all is not lost. You can pay for a relay service (smarthost), and relay all your mail through them, and they certainly have the requisite PTR record.

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I was actually planning on playing around with setting up my own mailserver at some dedicated host, such as or Could be a fun experiment and good learning experience. Thanks for that PTR tip. I'll keep that in mind! :) – Enchilada Jun 21 '11 at 14:10
@Enchilada I am not an expert with Linux servers, but I am with Exchange, and general principles of e-mail. So if you have any additional questions, add another comment with @KCotreau in it, and I will see it. If this answer helps, I would appreciate it if you would click the checkmark. – KCotreau Jun 21 '11 at 14:13

I do the same thing in gmail: I use when signing up for stuff.

Anything after the + is ignored by gmail - it will all still go to

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It's not really the same thing unless you can easily filter using rules. You can't just delete a + address. – music2myear Jun 21 '11 at 22:19
@music2myear: You can easily filter using rules. Under mail-settings (upper-right), create a new filter to delete messages To: Simple as that. – BlueRaja - Danny Pflughoeft Jun 21 '11 at 22:21

In addition to what Chris said it also depends on the IP of your host. I deal with customers who get go daddy domains and domains hosted in eastern Europe only to find out the IP is on 20+ blacklists. Of course you can petition the list to get off. But be careful some unscrupulous providers have their entire blocks black listed and some of the black lists will refuse to remove an IP originating from said block.

It's tough to tell what IP you will receive until you sign up, particularly godaddy has 100's of blocks that they may be pulling from. is a great resource for checking your blacklist status. Your best bet is to go with a reputable provider, hosting your relay from rack space or Amazon is great option since they can and will (I have personally seen it) change your IP if you are on a blacklist (unwarranted obviously).

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You probably won't have trouble getting in to other people's mailboxes anymore than if you had the email Most (all?) filter programs can't distinguish between and, provided that you have your email server set up correctly.

That being said, don't reinvent the wheel if you don't have to. Gmail has this kind of functionality built in, simply add a + after your real email address, followed by an arbitrary string of characters:

Then, you can filter messages from this domain in whatever way you wish. Go to account settings -> filters and add a filter for emails that are "To:" the newly created e-mail address.

However, there is a caveat with the above technique: some sites, whether intentionally or by accident, do not accept emails with a + in them. Thus, you might think that you have to give over your email to this scummy site that does not accept your +. Although this is obnoxious, because you can no longer use an arbitrary string of characters to identify the site, it is still workable. Gmail allows you to have an arbitrary number of dots (.) in arbitrary locations in your email address without affecting the "actual" email address. That is to say:

Is going to end up in the same mailbox as

Using this technique, you can generate "random" email addresses for scummy sites, even using the site name in the new email if the website allows all proper email addresses. If the website disallows + in email addresses, then you can add dots in random locations in your email in order to generate a "random" email. However, in the latter case, you have to keep track of where the dots are for which sites.

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I handle this a little differently. I created a yahoo group called something like I am subscribed, but no one else is. I hand out that address and when someone sends mail to it, they accumulate awaiting approval. Every so often I look through the senders and approve those who I want to hear from and the rest gets dropped in the bit bucket. The nice part is that Yahoo does spam filtering before forwarding to the group.

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Implementing a Sender Policy Framework SPF could also help.

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