While some issues are easy fixes, we recommend looking through our SpamStopsHere page to help you understand what could be causing the concerns you may face.

We believe that if you can provide us with more information as to the nature of your spam problem, provide us samples of spam if they are not bypassing our service, or take some measures on your end to prevent bypasses, that we can bring you to the 95% or even 98% or better level of spam being blocked.


Should I relay to my mail server's hostname or IP address?

During signup, our system will look up your existing "MX" records. You will see something like:

example.com   mail.example.com   10

In this example, you must then choose whether to use "mail.example.com" (the hostname) or (the IP address). Either will initially work, but there are subtle differences.

If your domain runs at a hosting company, then you are most likely using the hosting company's mail server for your email. In this case, use the "hostname". Hosting companies often change the IP address, but rarely change the hostname.

If your business has its own (in-house) mail server, then you may prefer to use the IP address. This will rule out any possible problems resolving the hostname to the proper IP address.

In any case, you can change it later from our Control Panel.

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After I sign up, how soon will SpamStopsHere be active?

Normally within 1 to 2 hours.

Any changes to your "MX" records do not take effect immediately, but must propagate through the Internet. MX records have a TTL (Time-To-Live) value which specifies how quickly changes will take effect. A typical TTL value is 12 hours, but your domain may be configured with another value, such as 24 hours. Some DNS servers may not honor the TTL, it can take up to 72 hours for the majority of your email to start passing through our service.

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Should I Whitelist SpamStopsHere in My Existing Spam FIlter?

As a new SpamStopsHere customer, we recommend that you whitelist our mail servers in your existing spam filter before switching your MX records. That will prevent your spam filter from blocking us until you can safely disable it. See the SpamStopsHere Quick Start Guide for more information.

If you feel that you need to keep your existing spam filter enabled permanently, contact our 24/7 support team by phone, chat or email anytime. We come up with a simple solution to help you avoid running two antispam systems.

How to Whitelist our Servers
  1. Login to our control panel
  2. On left navigation bar under Hosted Services, click SpamStopsHere .
  3. For each email domain under Options:
    1. Click Configurations Options
    2. Under Mail Server Settings, select Firewall.
    3. Add the list of "Current IP Addresses" to your existing spam filter's whitelist.

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Does SpamStopsHere offer a challenge/response system?

Please read our complete documentation / article over Challenge Response Systems for more information.

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Do you have a reseller plan?

Yes! If you're interested in reselling our services, please contact sales team or visit our reseller program page to apply for a reseller account.

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Is there a limit on the size of email attachments with your service?

Our email servers will relay email messages up to 100MB in size.

8-bit attachments can grow by up to 33% when converted to 7-bit MIME encoded content, which is required for e-mail transmission.

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Does your anti-virus work with Microsoft Exchange?

Yes! SpamStopsHere works with any mail server software that is already accepting Internet email, including Microsoft Exchange, Office 365, Google Apps Gmail, Lotus Domino, Sendmail, etc.

Here are pages with more details over Exchange Server & Exchange Online, Office 365 and Google Apps Gmail

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Will the service work with any web/email hosting provider?

If your organization has its own internal mail server, you or your IT staff can certainly, and easily, configure it to work with SpamStopsHere.

If your email service is hosted with an ISP or web/email hosting provider, this may vary. SpamStopsHere should work with most business oriented hosting companies, as a lot of businesses do maintain their own office mail servers and often require custom MX records. If a hosting company is in this market, they are probably used to having customers request MX record changes. Changing MX records is usually a trivial operation for a hosting company.

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Do I need my own mail server?

No! You only need your own domain name.

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Should I re-route blocked spam to a special mailbox?

Spam can either be fully REJECTED, or it can be FORWARDED to a special mailbox, such as spam@example.com for review.

If you are new to our service and leery of false positives, you may want to forward your spam to a spam mailbox for review until you are confident of our accuracy. Once you become comfortable with our accuracy, change the filter action for our more accurate proprietary filters to REJECT.

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What happens if I discontinue the service?

Canceling the SpamStopsHere service is as easy as implementing it. Simply remove the SpamStopsHere load balancer's from your domain's DNS MX records and list your actual email server (or new anti-spam service) in the MX records instead. After the DNS changes propagate (we recommend waiting 72 hours), you should then be able to cancel the SpamStopsHere service without any interruption of email.

Discontinuing service before removing the SpamStopsHere load balancers from your domain's DNS MX records may result in email sent to your domain being undeliverable.

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Can you monitor my switch-over, just to be sure?

Yes! We monitor all new signups! We regularly check the MX records of new signups until we see that our service has been activated; we then check our service log files to make sure everything is working correctly. We will immediately call you if we see a problem or potential problem.

We encourage you to call us so that we can answer your questions and address your concerns.

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Does the SpamStopsHere service delay my email?

Not noticeably. This service may delay your email by a few seconds. Email with large attachments, especially if you have anti-virus service, can be delayed up to about a minute. Since spam is processed in realtime as they arrive, it will cause less of a delay than many anti-spam products that process messages at intervals after they have arrived.

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Do you have backups of my email in case I need it?

No. SpamStopsHere service does not create a copy or backup of your email messages. If you are in need of a backup / archive we do offer RestorEmail Archiving to fill this void.

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How secure is the privacy of my email?

The SpamStopsHere service does not affect your security in any way. Our service does not backup or make copies of your email messages. The log files only contain the email addresses of the sender and the recipient. We will never log the entire email message. As described in our privacy statement, we do not share any information with anyone else.

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Can you change the MX records for me?

No, that is the only part we cannot do. Only you and/or your hosting company have (legal) access to your MX records. How to change my MX records.

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What if I don't know how to change my "MX" records?

That is no problem, We will email you the necessary changes and you can simply forward this email to your hosting company or IT department to make the changes or use our How to change my MX records article to make the changes yourself.

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How do you define spam with regards to the SpamStopsHere service.

Spam is typically defined in the anti-spam industry as Unsolicited Bulk Email (UBE). This includes any email that you receive that was unsolicited (you didn't initiate or subscribe to) and sent in bulk. As a result, if someone sends you a copy of a resume, or other targeted unsolicited personal email that is not sent in bulk, we can not block it globally as "spam", even if it may be unwanted by you. You can take advantage of the Personal Blacklist feature to block any harrassing emails that are not UBE. However, we recommend that you simply ask the party to refrain, and contact the sender's Internet Service Provider (ISP) or your local law enforcement if the harrassment continues.

Although it is usually obvious whether a message was targeted directly to you or sent in bulk, if you're unsure, please ask one of our analysts for assistance.

When discussing UBE and using the term spam, it should never be spelled in all upper case (SPAM), as this is a trademark of Hormel Foods Inc.

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Why is my outgoing email being blocked by AOL, Yahoo, and Hotmail, etc?

If you are using SpamStopsHere's outgoing filtering service, no email should be blocked by AOL, Yahoo or Hotmail for DNS-related reasons, as our DNS is properly configured.

However, users who choose not to use our outgoing filtering service need to be particularly careful when configuring their DNS SPF records. Specifically, when removing your email server from your MX records (one of the last steps in configuring your SpamStopsHere service) it is important to remember that your SPF records should not include any servers listed in your MX records, as those servers will not be sending mail out for your domain (their job is to handle inbound mail, not outgoing mail). Instead, make sure that your SPF records list your actual outgoing email server, ensuring that it is authorized to send email for your domain.

General Information (Not using SpamStopsHere's outgoing filtering)

The most common reason for AOL, Yahoo and Hotmail to block an organization's email is based on simple DNS configuration issues. These ISPs require that DNS be configured to ensure the following:

  1. The public IP address that connects to the ISP's mailserver has a DNS PTR record. This is suggested by informational RFC 1912.
  2. The hostname that your outgoing email server advertises in its SMTP HELO resolves. Required by section 3.6 of RFC 2821, which is on the standards track.
  3. Email is coming from a mailserver authorized by the domain’s DNS SPF records to send email for the domain listed in the sender's email address. This assumes that the domain has SPF records. Discussed in experimental RFC 4408.
  4. The domain listed in the sender's email address has DNS MX or A records that resolve. Required by section 3.6 of RFC 2821, which is on the standards track.

AOL has policies and procedures in place that allow them to blacklist your mailserver if more than 1:1000 email messages from your server are reported as spam by AOL users. It is very difficult if not impossible to be removed from this blacklist. If your organization sends bulk email, it is strongly suggested that you take advantage of AOL's feedback loop and follow SpamStopsHere’s recommendations.

Hotmail has a tendency to put outgoing email into the recipient's junk folder if you don't include the recipient's email address in the To: header. It is recommended that you ask your Hotmail newsletter subscribers to whitelist your sending email address.

AOL, Yahoo and Hotmail don't make these checks, but some recipient mailservers make the following checks which are often used to try to block spam in a very error prone manner:

  1. Does the hostname in the HELO resolve to the public IP address making the connection? Not mentioned in any RFC.
  2. Does the hostname advertised in the HELO appear in the DNS MX records for the domain in the sender's email address? Not mentioned in any RFC.
  3. Does the IP address making the connection match the IP address of one of the mail exchangers listed in the DNS MX records for the domain in the sender's email address? Not mentioned in any RFC.
  4. Does the PTR record for the public IP address making the connection resolve to a hostname that resolves to the public IP address making the connection? Not mentioned in any RFC.

Therefore, when possible, please try to configure your mail system to satisfy the above four checks to maximize delivery.

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What is the Tarpit filter (filter rule #17)?

If you let us know what email addresses at your domain are valid, we can provide a certain level of protection against directory harvesting attacks.

For example, if an email message is sent to 10 different email addresses at your domain, and at least three of them are invalid, we reject the remaining 7, even if they were to valid email addresses. These 7 email messages were "tarpitted". This helps prevent the spammer from determining which of the 10 email addresses may have been valid, as we report to the spammer that all of them are invalid.

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Why is my third party anti-spam product identifying spam that you are not?

If you are using an additional anti-spam product along with the SpamStopsHere service, there are typically two reasons why the third party filter may be identifying spam messages that SpamStopsHere did not identify as spam.

  1. The message may have bypassed the SpamStopsHere service altogether (the message did not even pass through our filters). Please click here for more information on bypasses.
  2. Many anti-spam products rate all (or most) messages as possibly being spam. Please make sure that your anti-spam product determined that the message was absolutely spam and not just 10-90% likely to be spam.

Many of these products that use Bayesian and other heuristics will determine that most of your email is spam, including legitimate email. In these cases it's normal for most of your email to be identified as spam, especially mail from new senders (potential new clients). We do not recommend simply marking all email from new potential clients as spam, and recommend that SpamStopsHere not be used with other anti-spam products, as you will just encounter more false positives. If our service is not blocking 98% of your spam, we're happy to work with you to resolve any problem. Please click here for a list of the most common causes when not receiving expected service levels.

Although it is true that Bayesian and other filters that use heuristics are occasionally able to guess that some types of email are possibly spam when SpamStopsHere did not, you will find that in the long run our filtering will be more accurate. Bayesian and other heuristic filters have different weaknesses than content based filtering, but you should find that the weaknesses inherent in content based filtering are more acceptable.

In addition, Bayesian and other heuristics typically only tag such messages as "possibly spam". This means that you will still have to review the messages, since it’s just a guess as to whether the message is actually spam. You don't want to miss any important emails because your software guessed that an email from a new client was 51% likely to be spam.

The type of filtering we do is the next generation in anti-spam filtering - we actually determine for certain that a message is either spam or is displaying characteristics reminiscent of a spammer. A respected independent reviewer, Ron Anderson (of Network Computing), reviewed the top 30 anti-spam products in the industry and rated ours #1 for accuracy.

Please also see our article on challenge/response systems.

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Spam being sent to my domain has increased, so the 1-2% of spam that you don't identify has increased. What's going on?

Many people believe that solving a spam problem can be accomplished simply by subscribing to an anti-spam service. However, it's typical for most domain owners to actually notice an increase in their spam problem as time goes on. Subscribing to an anti-spam service simply deals with that problem for you. Once you unsubscribe from the anti-spam service, you'll likely notice that you're getting even more spam than before.

Your spam problem doesn't go away simply by subscribing to an anti-spam service. If your anti-spam service blocks 99% of your spam, if the spam being sent to your domain doubles, you will notice that the amount of spam that reaches your inbox will double. The anti-spam service is still as accurate as it was before. Your domain is simply getting more spam.

There are steps that you can take to help slow down your increasing spam problem, and it is very important that you take these measures.

  1. Subscribe to your domain name registrar's privacy service so that you don't have to list a public email address in your domain's WHOIS information. It's more important to do this for new domain name registrations than for existing ones.
  2. Don't list any email addresses on your web site in plain text. Use a contact form, or hide the email address in an image (readable by humans but not by computers), and don't use a mailto hyperlink unless it's obfuscated by Javascript. The CAN-SPAM act of 2003 only makes it illegal for spammers to harvest email addresses from your web site if your web site includes a notice that you don't grant them permission to do so. The notice should read "The operator of this website or online service will not give, sell, or otherwise transfer addresses maintained to any other party for the purposes of initiating, or enabling others to initiate, electronic mail messages".
  3. Do not confirm your email address to spammers by viewing sourced images in their HTML emails or by being vulnerable to other embedded tracking methods.
  4. Do not confirm your email address by replying or trying to unsubscribe from spam. Instead, report the spam to the spammer's ISP.
  5. Be careful about who you give your email address to. Do not use your email address to enter sweepstakes, and tell others not to share your email address with free greeting card sites and other "email this to a friend" forms.
  6. When asked for your email address by a new organization, make up an email alias just for them. For example, if your email address is john@yourdomain.com, you're signing up for an account with Walmart, and they ask you for your email address, create an email alias of walmartjohn@yourdomain.com that forwards to your email account. Then give them that address. If you start getting spam sent to that address, not only do you know who sold your email address, but you can remove that email alias to stop the spam.
  7. Make sure that your email server has the capability to stop directory harvesting attacks. As a SpamStopsHere customer, if you take advantage of our Mailboxes List feature, we can do this for you.

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What is the difference between an unwanted virus email and an unwanted bulk email message?

UBE (Unsolicited Bulk Email)/Spam is blocked by the anti-spam service, and viruses are blocked by the anti-virus service.

Beyond that, spam is blocked based on it coming from spammers or advertising known spammer contact methods. These blocking methods can't be used for viruses. Virus emails typically come from innocent but infected hosts and not spammers. Additionally, they don't advertise known spammer contact methods. Usually the only way to determine that a virus infected email is a virus (and hence, unwanted) is by determining whether it contains a virus. As a result, the only way to block virus infected emails is by scanning it for viruses with the anti-virus service.

As a result, although virus email messages may be unwanted, they are not considered spam, and can typically only be blocked by signing up for our anti-virus service.

It is common in the anti-spam/anti-virus industry that they are separate services. Anti-virus service is typically billed separately as it does require more server resources and licensing fees for anti-virus software must be recouped.

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Why does somone trying to send me email get a "Domain of sender address does not exist" error?

That usually means that the sender's domain (the part after the "@" symbol) isn't capable of receiving email.

This error message usually will only occur if the nameservers for this domain are reachable and answering queries but clearly announce that the domain doesn't have any MX records and doesn't resolve to an IP address (NXDOMAIN).

This makes any bounce or reply messages impossible, and the sender's email address is considered invalid.

If the DNS servers are having temporary problems, and aren't answering for the domain, the message would only be delayed. It's only when the DNS servers for the domain authoritatively state that the domain can't receive email that one will get this message.

The sender should be specifying a valid email address when sending an email message. If the message doesn't require a reply (such as a Delivery Status Report), it should be sent from a null sender address. It is quite normal for recipient mail servers to reject messages if a reply can not be sent.

It is considered better to require the sender to correct any problems on their end and resend the message than to receive a message and not be able to reply to it.

This check is done prior to any whitelisting/filtering.

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What characters are allowed when specifying custom REJECT messages?

Letters a through z, A through Z and spaces hyphens (-) periods (.) exclamation marks (!) and at symbols (@)

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I've changed email hosting providers or my email server has changed, what do I need to do to use SpamStopsHere with these changes

Using SpamStopsHere actually makes it easier to change your email server, or your email server's IP address.

When making any changes, make sure that you leave the SpamStopsHere load balancers listed in your domain's DNS MX records. This will ensure that mail sent to your domain continues to be delivered to the SpamStopsHere service.

You will also want to enable the Message Queue (Store and Forward) Email feature within the SpamStopsHere control panel. This will ensure that your email is queued on our servers, and we do not attempt to deliver to a mailserver that is not currently online.

Once the new email service is configured (and tested) to accept email for your domain and users, simply change the "Customer Mailserver" setting in the SpamStopsHere Control Panel for your domain to the new email server. This is the setting that tells SpamStopsHere where to send your email after it is filtered. Changes take effect within 10 minutes. At this time you can disable the Message Queue Email feature. Your email will now start to deliver to your new mailserver within 10-15 minutes.

If you have the "Customer Mailserver" set to an IP address and are just changing the IP address of your email server, you don't have to worry about DNS caching issues. You can simply change the "Customer Mailserver" setting to the new IP address and we will deliver your email to the new IP address within 10 minutes. No need to worry about your domain record's TTL (Time To Live).

Important note: If you have the "Customer Mailserver" set to a hostname and change the IP address that the hostname resolves to in your DNS (rather than changing the "Customer Mailserver" setting), you will encounter DNS caching issues. In this situation, our servers will continue to deliver email to the old IP address for the hostname for at least as long as your domain record's TTL or up to 72 hours.

Depending on your email transition strategy, changing email servers can be quite problematic, as your users may need to check their email on two different email servers during the transition. The SpamStopsHere service doesn't make this part any easier, and it can take quite a bit of planning on your part for a smooth transition to a new email server.

We recommend that you leave the SpamStopsHere load balancers in your domain's DNS MX records. Sometimes, however, when switching to an email hosting service that also administers your domain’s DNS, the new provider will make changes to your MX records. It is important to follow up with them to ensure that they keep SpamStopsHere’s load balancers in your domain's DNS MX records. If you should lose the DNS configuration, you can find the recommended DNS MX settings for your domain in the SpamStopsHere Control Panel under "View Recommended MX Records for your domain".

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