It used to be that one of the must frustrating mistakes a GMass user could make was accidentally clicking the regular Gmail Send button instead of the GMass button.

Clicking the Gmail Send button by accident exposes members of your email list to each other and breaks personalization.

Numerous GMass users have at some point accidentally clicked the blue Gmail Send button when they meant to click the red GMass button.

The GMass Chrome extension now hides the regular Gmail Send button in certain situations and confirms intent in other situations.

Specifically, if there are more than 20 email addresses in the To field, or if there’s a GMass alias address in the To field, the Send button will be hidden.

If, however, you have more than one Compose window open, then the Send button will NOT be hidden. If the Send button is present, and you have more than 10 email addresses in the To field, and you click Send, you’ll get a popup asking if that’s what you really meant to do, with an option to cancel the send.

We attempt to hide the Send button because we assume that if you have more than 20 addresses, it is likely that you mean to use the GMass button to send individual emails to each email address rather than the Send button where all of the email addresses would be exposed to each other.

If, however, you want the Send button back after it has been hidden, you can easily make it re-appear. Just add the special email address as the last address in the To field, and within a second, the Send button will re-appear and will remain in that specific Compose window.

You can then remove the address if you wish.

The default tracking domain that GMass uses for open-tracking, click-tracking, and the unsubscribe link for Google Apps users,, was deemed suspicious by Google for a period of about 36 hours this past weekend. The domain has since been cleared and is now functioning properly, but there are some points to consider.
On Friday morning, May 27, several users reported that the domain, was redirecting to a phishing warning page that looks like:

For GMass Google Apps users, is the domain that is used inside your email campaigns to make open tracking, click tracking, and the unsubscribe link work. A different domain is used for regular Gmail accounts, so this particular issue only applies to Google Apps Users.

What does this mean?

It means that during the time that Google had listed as suspicious, some links to would take the recipient to the “Deceptive site ahead” page above instead of the actual URL. For GMass users, that means that links in email campaigns that have been click-tracked and unsubscribe links may result in your recipient being taken to this page instead of the intended page. From the “Deceptive site ahead” page, the user does have the option to proceed to go to the final URL.

The issue was temporary, and Google removed from the suspect list as of Saturday evening May 28.

As soon as we became aware of the issue, we took two steps:

  1. We disabled the redirects from to the specific phishing site in question and reported the corrective action to Google.
  2. We switched the default tracking domain for Google Apps users from to It means that all campaigns sent after we made the switch would use, but all campaigns sent before the change will still have recipients clicking links that include

Why did this happen?

It happened because a single user, a phisher, used GMass to sending a scammy email, and activated click-tracking to obfuscate the destination URL. The destination URL, which Google determined was a phishing site, has since been removed from the Internet.

Why did GMass allow this phisher to use GMass?

GMass is not a traditional Email Service Provider like MailChimp or JangoMail, where a team of people approves and rejects accounts based on the user’s information. GMass is a fully automated system, and we intentionally do not police our users because:
  1. We rely on Gmail’s own spam detection mechanisms to terminate users that are abusing GMass, and therefore abusing Gmail.
  2. We could never build a better abuse detection system than Gmail already has. Gmail has been doing this for much longer than we have and has access to much more data than we do to make decisions as to whether accounts are legitimate or abusive.
I consider it one of the great benefits of GMass. For you the user, you get the world’s highest deliverability because your emails are being sent from Gmail’s email servers. For me, as an operator of an email marketing service, I don’t have to employ people to police users and approve/reject accounts.

What does this mean for me, a legitimate user?
It means you should take a step to isolate yourself from the behavior of other users. There’s only one step you need to take to protect yourself from the potential bad behavior of other users. You should set up your OWN tracking domain that is used in the open tracking, click tracking, and unsubscribe links. That way, instead of appearing, your own domain will appear. Your own tracking domain can be a sub-domain of your organization’s domain. Click here to get started.
What about IP addresses? Do I need to make sure GMass’s sending IPs aren’t blacklisted?
No. GMass is built on top of Gmail, and all emails are sent from our users’ own Gmail accounts. That means that the emails are sent from Gmail’s own IP addresses, which are the highest deliverability IP addresses in the world. GMass is again different from a traditional ESP in this regard. A traditional ESP like MailChimp or JangoMail maintains its own sending servers and therefore its own IP addresses. They must police their users to keep their IP addresses clean. Because GMass is built on top of Gmail, however, we rely on Gmail to kick spammers off their network to keep their IP addresses clean, and they do an excellent job of this.
Most GMass users know that you can send a personalized mail merge campaign using GMass and your Gmail account with a Google Sheets spreadsheet. Any of the columns in the spreadsheet can be used to personalize the Subject and Message.

Did you know you can also personalize the Cc and Bcc fields? Meaning, you can have each individual email message Cc’d or Bcc’d to an email address associated with the address you’re sending to.

An example: You’re sending 100 emails to 100 of your customers, but you want each email to be Cc’d to each individual customer’s account manager. Each of the 100 customers has a different account manager, so you can’t just enter a single email address in the Cc field of the Gmail Compose window. Instead, create a column called “cc” in the spreadsheet you’re using, and specify the account manager’s email address in the “cc” column.

Your spreadsheet might look like this:

A spreadsheet with a “cc” column. The email address in the “cc” column will be used as the Cc for each email sent to the “EmailAddress” column. Note that the “cc” column comes after the “EmailAddress” column.

Make sure that the “cc” column comes after the column with the actual recipient email addresses so that GMass doesn’t accidentally use the “cc” column as the recipient To addresses (since GMass auto-detects the column containing recipient email addresses).

When you connect to the spreadsheet inside Gmail, the Compose window will be launched with the recipient addresses in the To field.

The Cc field will show as blank, but as long as you have a “cc” column in your spreadsheet, each email message will be Cc’d to the address from the spreadsheet.

The “Cc” field in the Gmail Compose window will remain blank.

Similarly, you can set a personalized Bcc address by creating a column called “bcc” in your spreadsheet. Again, make sure the “bcc” column is to the right of the column containing the actual recipient email addresses.

One of the most frequent emails I answer from users is:

I was testing your open-tracking, and I know that certain emails weren’t opened, but GMass still reports them as having been opened.

99% of the time this is because the user opened his own sent emails from the Sent Mail folder in Gmail. Doing so triggers the download of the open-tracking pixel, which is how GMass, or any email marketing system, knows if an email is opened. Opening the email up from the Sent Mail folder is equivalent to the recipient opening the email from his/her own Inbox.

Additionally, if a particular email address bounces, and you open up the bounce notification, and the original email is underneath, then an open could be triggered also because you’re now viewing the original email underneath.

Another scenario: you set GMass to just create Drafts for a campaign rather than actually send the emails. You then open each Draft individually to customize it. GMass will count you opening the Draft as the recipient opening the email.

How do we solve this?

I have some ideas as to how to provide more accurate open-tracking results in this particular scenario, but none is a perfect solution. Given that we’re integrating email marketing into a Gmail account, this system is by nature different from a traditional email marketing system like Constant Contact or MailChimp, where the user would never have access to the actual sent email, and therefore couldn’t accidentally trigger an open.

The primary method I can separate opens from the user in his Sent Mail folder from opens by the recipient in his Inbox is by recording the IP address that the user uses to trigger the email marketing campaign, and then treating subsequent opens that originate from that IP address as suspect. Even this seemingly simple solution, however, could lead to invalid reporting data. If in an office, there are 100 people working at their desktops, and the office has an Internet connection such that all 100 people share an IP address, and one person uses GMass to send a mass email to all 100 people, then it would be expected that legitimate opens come from the same IP that the sender used to trigger the mass email.

Therefore the best solution may be to count opens from the same IP as the sender as “suspect” and flag them appropriately, but let the user decide if they are legitimate opens or not. Enhancing reporting in this way is on my GMass product roadmap.

If you’re a G Suite or Gmail user using GMass for your email marketing campaigns, you may notice that the domain or is used in your emails’ open tracking, click tracking, and unsubscribe link elements. For example, if you hover over a tracked link before clicking it, and notice the URL that it points to, you’ll notice that it points to, and then this redirects to the actual destination URL.

Now you can swap out the default tracking domain for your organization’s own domain. If your domain is, for example, you can set up, or or and use that branded tracking domain with GMass. There is some technical setup required to make this happen though. Specifically you have to add a DNS record — a CNAME record with your chosen host aliasing to “”. Note that this used to be but we’ve recently changed it to

How to Set Up

First, create a CNAME record for your chosen host such that the tracking domain aliases to If you don’t know what a CNAME record is, you may need to consult your webmaster or domain administrator. Here’s a Google Support page on how to set up a CNAME record.

How do you know if you’ve set up the DNS record properly? Try “pinging” your tracking domain and see if the IP address is pinged. On Windows, open up a Command Prompt and type “ping your-tracking-domain”. On a Mac, open up Terminal and do the same. I’ve set up to be the tracking domain for my own GMass account, for example, so I “ping” and see if the ping shows a connection to

In this case, I’ve set up the tracking domain “”. To test my DNS record, I ping and look for a successful connection to

After you’ve completed the DNS setup, you must submit your tracking domain to GMass.

If you don’t have control over your domain’s DNS…

If you don’t have the ability to set up a branded tracking domain, but still want to isolate yourself from the behavior of other users, you can register one from scratch.

What are the benefits?

There are two benefits to setting up a branded tracking domain:

1. A branded tracking domain creates a more trustworthy impression to your email recipients. Savvy Internet users hover over links before clicking them, and seeing the domain with which they’re familiar (your organization’s domain) as opposed to GMass’s default tracking domain can go a long way in increasing trust, and ultimately increasing your click-through rate. The world’s biggest brands use ESPs (Email Service Providers) to send their email marketing campaigns, and they all employ branded tracking domains instead of the default Email Service Provider tracking domain.

2. Setting up a branded tracking domain isolates your reputation from the reputation of other GMass users for deliverability purposes. Meaning, if a spammer uses GMass, and the spammer’s emails contain the default GMass tracking domain, and this causes the default tracking domain to be listed by a domain-based spam blacklist, and if your emails contain the same tracking domain, the deliverability of your emails could be affected. If, however, you set up a branded tracking domain, that only your users use, you can protect yourself from being adversely affected by another user’s actions.

Are you a regular Gmail, not a G Suite user?

Even if you’re not a G Suite user, you can take advantage of this feature if you manage your own domain and send email campaigns with GMass from a regular Gmail account (your email address is or The default tracking domain used for regular Gmail accounts is “”, but if you manage your own domain, you can assign a branded tracking domain to an individual Gmail account similarly to how you can assign a branded tracking domain to an entire Google Apps domain. Follow the same setup procedures outlined here.

Since I launched GMass about nine months ago, several users have asked me to make it possible to email duplicate email addresses in a Google Sheets spreadsheet. While in most cases, a user prefers that GMass de-dupe an email list, there are certain cases where de-duping isn’t appropriate.

Now when you connect to a Google Sheets spreadsheet, there is a checkbox you can check which will allow you to keep duplicate email addresses.

There is a new checkbox to “Keep Duplicates”.

If the Keep Duplicates option is checked, then GMass won’t de-dupe your email addresses, and you can send multiple email messages to the same email address, with different values from the different rows in the spreadsheet. For example, let’s say you’re an after-school activities program, and you’re emailing the parents of children who are registered for a program. A parent might have multiple children registered, and therefore the parent may need to be sent several personalized emails, all at the same address, one with each child’s registration information.

An example of a spreadsheet where you don’t want to de-dupe your list before emailing.

In the spreadsheet above, the parent “Joan Smith” has three children registered for three different classes. In this case, the program administrator wants Joan Smith to receive three different emails, one with each child’s class registration information.

Note that when the Compose window is launched, the multiple instances of the address are slightly altered by GMass so that GMass can associate each address to the right row in the spreadsheet. This is normal, and you should not alter the “-GMassX” tag that is added before the @ sign. When the emails are actually sent, these are removed from the email address.

After GMass connects to a spreadsheet and “keeps duplicates”, multiple instances of the same email address are tagged.

Several users have recently reported seeing bounce backs from Gmail that look like this:

Delivery to the following recipient failed permanently:

Technical details of permanent failure:
read error: generic::failed_precondition: read error (0): error

We’ve seen bounces like this for both regular Gmail users and Google Apps users using GMass. The error is a non-standard bounce message that is specific to sending via the Google platform. What causes the error? Nobody is certain for sure, but the Internet speculates that it’s either one of the following:

  1. The remote server is rejecting the email due to an SPF failure. This is applicable to Google Apps users that are sending from their own organization’s domain, not from or
  2. The remote server is rejecting the email because Gmail’s sending IP is blacklisted, but Gmail doesn’t want the end user to know that’s the reason for the fail, so this generic message is delivered instead.
Regarding reason #2, generally we’ve seen that the deliverability through Gmail’s servers is the world’s best, but it seems that occasionally even Gmail’s servers get blacklisted.

Regarding reason #1, if you’re a Google Apps user, regardless of whether you’re using GMass, ensure that you have SPF set up correctly for your domain. That means you need to configure the DNS for your domain to allow email to be sent by Google’s servers on behalf of your domain. You can check if your domain is configured allow Google to send email on its behalf via this easy-to-use tool. Just input your domain, and check the results. I just checked my own domain,, which runs on Google Apps, and noticed an issue, which I’m about to fix:

The SPF record for breaks the rules by requiring too many DNS lookups.
In the case of’s SPF record, the record includes permission for Google’s servers to send email for, but here’s an example of a domain of a GMass user where SPF doesn’t include Google’s servers at all:
If you still see this bounce notification after ensuring correct SPF settings, or if you’re not a Google Apps user, it could be issue #2 at play.

How is GMass handling these bounces?

Since GMass categories all bounces and replies for you, and builds an internal Bounce List for your account in order to suppress future mailings to bounced addresses, we’ve added these bounces to our “Bounce Exception” list, meaning we won’t count addresses that bounce with this message as a true bounce. That means that future attempts to send to these addresses will still work.
We’ve also deleted all bounces that were on your account’s Bounce List in the past because of this issue.


Hi there! You were likely directed to this post from inside Gmail, because you attempted to “GMass” an email campaign while we are performing maintenance on our core servers. We are doing this because GMass has been slower than we like over the last couple days, and we’re putting in some measures to speed things up.

The email you just sent has been received by GMass and is in a holding area until our maintenance is over. At that time, it will be sent just like normal.

The maintenance period began at 5/11/16 7:40 PM CST and should be over by 5/11/16 8:40 PM CST.

If you have any questions, email us at support AT

Update 8:29 PM CST – the maintenance period is over and all queued emails from the maintenance period are sending now.

The GMass Settings box, popped open in a Gmail Compose Window.
The GMass Settings box, popped open in a Gmail Compose Window.

Below is detailed explanation of each item in the GMass Settings box, which is accessible by clicking the “up” arrow next to the GMass button.

Send Test: Pretty self explanatory, but this option sends a test email to the address of your choice. Whatever is currently in the Subject/Message will be sent as a test email. Additionally, the test email message will include personalization if there is personalization information available for the test email address. Meaning, if you’re connecting to a Google Sheets spreadsheet to do a mail merge, and the test address is one of the addresses in the spreadsheet, then the test email will include personalization. Or, if the test address is a Gmail contact, and the address is part of the To field already in your Composed message, then sending a test to the address will include First/Last name personalization.

Live Proofreading: As of May 2017, you can now submit your email campaign for proofreading by a live human editor. Editors are standing by 24 hours a day and will correct your email for spelling, punctuation, grammar, and improve word choice, sentence structure, and organization. More details on the GMass live proofreading service.

Inbox Spam Promotions: This button, indicated by “Inbox or Spam?”, is a way to test if your email is likely to end up in your recipients’ inboxes, spam folders, or promotions folders. It works by sending this email out as a test to several test email addresses across a variety of accounts and seeing which of these three types of folders your email landed in.

Load Content: This dropdown shows your past GMass campaigns (but not “test” emails). Choose a past campaign by its Subject and the Subject/Message of your Compose window will be set to that of your chosen email campaign.

Personalize: These buttons insert personalization variables into your Message. Note that you can also insert personalization variables into the Subject, but not by using the buttons. You have to copy/paste the personalization variables into the Subject. For more information, see the GMass Personalization Guide.

Google Sheets Personalize: These buttons will display only if you’ve connected to a Google Sheets spreadsheet to send this campaign, and has the same effect as the other personalization buttons described above. For more information, see the GMass Personalization Guide.

Unsubscribe Link: Inserts an unsubscribe link into your message, wherever the cursor is. The language of the unsubscribe link can be customized, but the actual URL should remain unaltered. For example, if you want to change the language to:

Please unsubscribe if you wish to never hear from us again

You can do that, but just link the appropriate words to this URL:

Track: Choose whether you’d like to track opens and/or clicks. By default, both are selected. If you choose tracking options, you can view who opened or clicked an email by accessing the GMass reports after you send your campaign. Just drill down into the “GMass Reports” Label on the left-side of Gmail.

Send as: New messages vs. Replies. The default choice is “New Messages”, which means that your email marketing campaign will send as a new email thread. If you choose “Replies”, your message will be tacked onto the last thread you had with each recipient. If you have never emailed a particular recipient in the past and therefore have no prior conversation, then the email will go out as a new thread.

Action: Send vs Just Create Drafts. By default, clicking the GMass button will send your campaign, one email to each address in the To field. However, if you want to spot check your messages before they are sent, you can choose “Just Create Drafts”. Only Drafts will be created, and no emails will be sent. You can then review them in your Drafts folder, and GMass will email you a link to click to either send or delete the drafts. Detailed information on Just create Drafts.

Suppression by Campaign: To set a suppression list for a campaign, just select the past campaigns whose recipients you want to eliminate from your current campaign. Any past campaign can be used as a suppression list for the current campaign. You can select a single campaign or multiple campaigns from the dropdown. Use the CTRL key on Windows or the Command key on a Mac to select multiple lists from the Suppression select box. Any email address that was part of the chosen campaign will be suppressed, or eliminated from, this current campaign. Detailed information on using Suppression Lists.

Suppression by Days: You can suppress recipients by the number of days since they last received an email from you. Detailed information on suppression by days.

Spread out – Emails/Day: If you want to space your email sends over a number of days rather than sending them all at once, you may do so here. You must use a minimum value of 25. If left set to “max”, which is the default, GMass will send as many emails as your account allows and save the rest for future days.

Spread out – Pause a few seconds: If selected, GMass will throttle your campaign and delay for 5 to 10 seconds after each individual email is sent. See this article on the throttling feature. You also have the option to set a longer delay of 60-90 seconds.

Auto Follow Up: Have reminder emails sent at designated intervals to those people that don’t reply to the message you’re sending right now. Choose the interval, and the reminder text that should appear at the top of the original email. Detailed information on the auto follow-up feature.

Schedule: Choose whether to send this current email NOW or at some time in the future. Additionally, if you connected to a Google Sheets spreadsheet, an additional checkbox called “Repeat daily…” will also be shown. Checking this box will enable the automated recurring campaigns feature.

This is a living document and is updated when new features are added to the Settings box.