Product Updates

Stay up to date whenever we change something

3/3/2024 6:03:39 AM Bounce filter adjustment: We discovered a new type of Gmail bounce that looks like this, "550 5.4.5 Daily user sending limit exceeded. For more information on Gmail sending limits go to". This bounce resulted from sending from an "alias from" address instead of the primary Google account, and when the SMTP server connected to the alias was a Gmail server, and when the account was over-limit. These bounces look new and have been appearing since mid November 2023. These bounces were erroneously resulting in the recipient address being placed on an account's bounce list. The filters have been adjusted so that these types of bounces are counted as "blocks" not bounces. Additionally, we've purged the affected addresses from everyone's bounce list.
3/2/2024 5:22:34 AM Extension bug fix: Previously long domains like could not be entered into the domain suppression box. This is now possible.
3/2/2024 5:14:21 AM Cancelling campaigns: When you cancel a campaign and its auto follow-ups, a more aggressive approach is now taken, where any pending batches of auto follow-ups that haven't completed sending yet, are now also cancelled. Before, any pending batches would be allowed to continue sending but any new batches would be prevented from being created.
3/2/2024 4:36:58 AM API: When retrieving a campaign's status via the and methods, "status" can now include the additional values of "cancelled", "paused", and "abpaused".
2/26/2024 3:34:38 PM Auto follow-up timing bug fix: If you had set specific times for your auto follow-up stages, and you had also set specific days, like Mon-Fri, when your campaign should send, and then an auto follow-up send fell on a Sat/Sun based on the "Stage Days", the campaign would send close to midnight Monday local time and not wait until it was the right time on Monday. This bug is now fixed.
2/24/2024 6:32:26 PM Spam Solver Improvements: The main functionality has a longer timeout period now such that if it takes longer than 30 seconds to send the email to all the seed accounts, it won't timeout anymore. Before the operation would sometimes timeout resulting in an endless spinning wheel without displaying the bar graph with the results.
2/20/2024 7:22:12 AM Sending: If you launch a campaign and the schedule gets pushed back because the current day is a holiday and you have "Skip Holidays" checked, then the confirmation message will indicate clearly that TODAY is a holiday. This is to clear up confusion about why campaign times are getting pushed back.
2/20/2024 7:21:18 AM Extension: Now when you check the "Skip Holidays" checkbox, a butterbar help dialog will appear in the lower-left.
2/20/2024 6:54:27 AM Auto follow-up bug fixes: Some auto follow-ups did not send entirely or did send but at the wrong time if they had one of the new skip-holidays or choose-holidays scheduling features set. Any affected auto follow-ups will go out in the coming days as close to the "correct" time as possible.
2/20/2024 6:53:24 AM Sending bug fix: If you had skip-holidays or choose-days set, and a campaign was in the middle of sending and the time crossed over into a disallowed day, the campaign paused but never resumed on the next allowed day. This is now fixed.
2/6/2024 7:47:32 AM API: The API methods to retrieve campaign data now include additional information. status: scheduled / sent / error / unknown. There's also a new parameter "lists" which includes information about the Google Sheets that were the source of data for the campaign.
2/6/2024 7:47:07 AM Auto-followups: The timing of auto follow-ups has been improved for campaigns that are paused and later resumed. Instead of auto follow-ups that are "past due" going out right away, they will wait until they are near the 24-hour interval of the prior auto follow-up stage.
2/6/2024 7:45:04 AM API: The method to send campaigns is now in line with the two new scheduling features, "Skip Holidays" and "Choose Specific Days". See "allowedDays" and "skipHolidays" here:
2/6/2024 7:44:19 AM Extension: Two new scheduling feature, "Skip Holidays" and "Choose Specific Days" have been added. Campaigns can now skip sending on holidays and only send on the weekdays that you designate.
2/6/2024 7:43:23 AM API: New method to retrieve campaign blocks has been added.
2/6/2024 7:42:52 AM A checkbox has been added to the dashboard settings, so that users of personal Gmail accounts who are sending through an SMTP server can use GMass's "from" domain replacement system to become DMARC compliant, even before Gmail changes its DMARC records.
1/25/2024 5:02:34 PM MultiSend update: The MultiSend dropdown has been updated to include the primary sending account as an account that can be selected or UNselected. This allows you to send a MultiSend campaign while excluding the primary account that you're logged into.
1/23/2024 5:04:00 AM If GMass DKIM signs your emails (only possible when sending over an SMTP service), and your email includes the List-Unsubscribe header, the DKIM signature will now be based on the two additional headers of List-Unsubscribe and List-Unsubscribe-Post.
1/23/2024 5:02:35 AM GMass will now include the List-Unsubscribe-Post header if you have the List-Unsubscribe header enabled in your settings. This header will always be set to "List-Unsubscribe=One-Click" if included, and it enables one-click unsubscribe functionality.
1/22/2024 8:50:16 AM When GMass writes a DKIM signature to an email that is being sent over SMTP (not native Gmail), then the email placed in the Sent folder of the account will also now contain the header showing the DKIM signature.
1/21/2024 10:41:39 PM Launched a DNS management system for users with personal Gmail accounts ( and who are also connected to an SMTP server. This is preparation for a change in's DMARC record that will no longer allow sending campaigns "from" accounts through external SMTP services.
1/16/2024 6:31:35 AM GMass Transactional SMTP Relay ( We've added a limit of 5 simultaneous connections per IP address and blocked several abusive IP addresses.
1/12/2024 6:44:54 AM The Reply Project: ChatGPT-generated replies have been updated to the "gpt-3.5-turbo-instruct" model.
1/6/2024 10:30:24 PM Bug fix: Affiliate sign-up form at wasn't working if user tried to sign up as an affiliate but ALREADY had a GMass account.
1/5/2024 5:34:40 AM Bug fix: When creating DRAFTs instead of sending, if an account had an SMTP service connected to it, and the account had DKIM configured inside GMass, if the DRAFTs were then sent via the account's SMTP server, the DKIM settings were ignored and the messages were not DKIM-signed. This is now fixed.
1/5/2024 5:05:24 AM Bug fix: The suppression "days" parameter wasn't working properly if an account was using MultiSend. The suppression list was being built based on only the MultiSend accounts' sending history and not the original sending account's history.
12/21/2023 6:30:12 AM Extension behavior change: Now, when you load a template from the dropdown in the settings box, if you choose to load only the Settings, the Friendly Name will not be set. You must choose to load the content (Subject/Message) for the Friendly Name and Preview Text inputs to be set. It was decided that the Friendly Name and Preview Text are more closely related to the Subject and Message than the campaign's other settings.
12/21/2023 6:29:12 AM Extension bug fix: If you had a friendly name or preview text set for your campaign, and then you cleared out the list in the To field, the friendly name and preview text would disappear. This won't happen anymore.
12/20/2023 4:19:11 PM Bug fix: Retrieving an account's entire unsubscribe list, either from the dashboard or API, was failing in some cases.
12/15/2023 2:37:53 PM List-Unsubscribe header: We are now forcing the header onto emails sent using our shared AWS SES SMTP account or our internal server. The header will be added in these cases even if you have the header turned off in your settings.
12/15/2023 2:11:01 PM SendGrid: If a user is assigned to our shared SendGrid account, campaigns can no longer be launched using SMTP as the sending option, due to SendGrid's suspension of our service with them. Users will see an on-screen error when attempting to send.
12/13/2023 5:33:05 AM Dashboard bug fix: Sometimes the recipient count for a campaign wasn't accurate, especially in cases where some recipients errored out and had to be re-tried later on.
12/2/2023 5:42:15 PM Affiliates: Launched a new affiliate sign-up form,, to replace the old process of signing up to be an affiliate.
12/1/2023 2:48:29 PM API: New endpoint added to retrieve unsubscribed domains. See
11/30/2023 11:31:09 PM New "holidays" settings page launched. Choose standard holidays and define your own custom holidays. This section doesn't technically do anything right now, but eventually there will be a "Skip Holidays" option in the scheduling settings of a campaign.
11/30/2023 11:28:59 PM Bug fix: On the individual campaign report page, the real-time Unsubscribes feed wasn't working for the last few hours.
11/30/2023 10:50:50 PM API: The "campaigns" endpoints return additional campaign data, including the "from" line, the campaign creation date, and the stage of auto follow-up if it is indeed an auto follow-up.
11/30/2023 12:00:00 AM Launched MultiSend reporting: Now in the dashboard and in the API campaigns using MultiSend can see a breakdown of stats by individual sending account.
11/30/2023 12:00:00 AM API: When sending a campaign via the "campaigns" endpoint, the campaign object returned will include details beyond just the campaign's ID.
11/29/2023 12:00:00 AM MultiSend settings page: Now shows whether each account is OAuth connected and checks to make sure SPF and DMARC are in place for each domain.
11/28/2023 12:00:00 AM Bug fix: Gmail Pub/Sub wasn't working for certain user accounts where they signed up, disconnected for a while, and then re-connected to GMass.
11/28/2023 12:00:00 AM New setting for bounces: Make bounces disappear instantly
11/28/2023 12:00:00 AM Bug fix: Sometimes when transferring a subscription, a user would get the wrong error, telling them that the transfer-to account doesn't exist when it actually did.
11/28/2023 12:00:00 AM Affiliates: An affiliate's earnings are now accessible via the dashboard.
11/27/2023 12:00:00 AM A "select all" checkbox has been added to certain data tables in the dashboard.
11/26/2023 12:00:00 AM Launched this Product Updates page!
11/18/2023 12:00:00 AM Campaign reports that are inserted into the "GMass Reports" Label will now have the timestamp of when they were generated, so it can be assessed if there's a delay between when the report was generated and when it arrived into the Label.
11/16/2023 12:00:00 AM Bug fix: When logged in as a team master, the user can now take action on its members' campaigns, like pausing/resuming/cancelling/archiving them.
11/16/2023 12:00:00 AM Gmail API began throwing "429" errors. Now campaigns will be auto-retried when they encounter this error.
11/16/2023 12:00:00 AM When an auto follow-up batch errors out, the notification will contain more detail about the error now.
11/15/2023 12:00:00 AM Stage 1 auto follow-ups have been delayed recently. Took steps to optimize speed.
11/15/2023 12:00:00 AM During peak times, the delay between launching a campaign and it starting to send was approaching 3 minutes. Adjusting our server launcher algorithm to bring this closer to 1 minute.
11/13/2023 12:00:00 AM Fixed bug where some "overlimit" bounces from Gmail were erroneously being classified as replies.
11/5/2023 12:00:00 AM Some users are being moved off of shared AWS tracking domains and onto a new set of shared tracking domains.
10/31/2023 12:00:00 AM MultiSend: Better logic to allow other accounts to continue sending when one account in a group hits its sending limit
10/30/2023 12:00:00 AM Bug fix: In rare cases, campaigns with both auto follow-ups and triggers were sending duplicate auto follow-ups to recipients where the trigger had fired
10/30/2023 12:00:00 AM Bug fix: SMTP relay was throwing errors on emails where the "verify" setting was on
10/26/2023 12:00:00 AM Bug fix: The MultiSend helpful butterbar message was appearing at the wrong time when configuring MultiSend settings
10/26/2023 12:00:00 AM MultiSend: Now works when launching campaign with "Create Drafts" option
10/25/2023 12:00:00 AM Bug fix: MultiSend "split factor" calculation was wrong
10/25/2023 12:00:00 AM MultiSend: Removing the aggressive unsubscribe/bounce filtering on campaigns unless Global Unsubscribes/Bounces is turned on
10/25/2023 12:00:00 AM MultiSend: Added butterbar help that appears when you check the box
10/23/2023 12:00:00 AM Better validation for the sending speed field when using MultiSend
10/23/2023 12:00:00 AM MultiSend: Adding aggressive unsubscribe/bounce handling
10/21/2023 12:00:00 AM MultiSend: If campaign is rerouted to user's SMTP server, MultiSend features are now disabled
10/21/2023 12:00:00 AM MultiSend: Validation improvements for emails/day setting. Can now set more than 2,000/day.
10/18/2023 12:00:00 AM Bug fix: Launching a mass forward to a list from a Sheet wasn't working after MultiSend was introduced
10/14/2023 12:00:00 AM Poll improvements: Filtering out bot clicks, and now recording User-Agent and IP for each poll response
10/14/2023 12:00:00 AM You can now cancel a campaign even if your Google account has a broken OAuth connection to GMass
10/14/2023 12:00:00 AM The Reply Project: Delete button wasn't working when viewing campaign-specific replies
10/2/2023 12:00:00 AM The Reply Project: Archive/delete buttons now work with MultiSend campaigns

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