Throttle your email campaign (add delays/pauses between messages) [Updated 2026]
You can now choose to throttle your email campaign, adding a few seconds of pause after each individual email is sent. This is instead of the default way of sending…
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Gmail increases email size limit to 50 MB, but there’s a catch…
Gmail announced yesterday that the email size limit has been upped from 25 MB to 50 MB, but there’s a catch — it’s only for RECEIVING emails. Meaning, if…
Why your mass email sent to fewer recipients than you expected
If you’ve sent a mass email with GMass by copying and pasting addresses into the To field, and fewer emails were sent than you expected, then the reason…
Why your Gmail mail merge personalization failed
If you’re sending mail merge campaigns in Gmail with GMass, or even a different mail merge service, there are several reasons why personalization may fail. If you find that…
You can now restore a deleted Gmail Draft
GMass uses Gmail Drafts as the storage mechanism for every mail merge campaign you send. After GMass is finished sending the mail merge campaign, it deletes the Draft, because…
Pay for Gmail Mail Merge with PayPal
You can now pay for GMass, the ultimate Gmail mail merge tool, with PayPal. We recognize that many of our international users don’t have access to credit cards,…
How to use a Google Sheets spreadsheet as a dynamic email suppression list
Note: The technique in this article is now deprecated. There’s a MUCH easier way to do this using GMass’s dynamic lists. When sending mail merge campaigns in Gmail…
How to create a GMass account
It might seem strange that 18 months after I launched GMass I’m writing a post about how to create a GMass account, but with our ever-growing user base,…
The Campaign Report and the Message are now linked to each other
We’ve just deployed an enhancement to our mail merge tool such that you can easily view a campaign’s content while viewing a Campaign Report, and similarly, you can…
How to troubleshoot a missing GMass button
If you suddenly find that the GMass button has disappeared from your Gmail interface, this guide will help you. First, determine if the extension is failing completely or…
How to Manage Your Team Plan
If you’ve subscribed to a Team Plan, you’ll want to manage the members of your Team. A team plan allows you to subscribe one account that is the…
How to edit a campaign
After you’ve launched a campaign, you may wish to edit it either before it actually sends or perhaps in between batches of sends. To edit a mail merge campaign:…