Core workflow

Mailboxes

A mailbox is the email account OSENBOLT sends from. This page explains how to connect one, how limits work, and how to keep it healthy.

About 7 min read

How sending works

OSENBOLT sends through your own email account, not through a shared mass-mailing server. That means your emails come from your real address and arrive like a normal message. The trade-off is that you inherit your account limits and your account reputation, so treating the mailbox well matters.

Connecting a mailbox

Gmail and Google Workspace

Choose Gmail and sign in with Google. You grant permission for OSENBOLT to send and read mail on your behalf. The connection uses secure tokens, and you can disconnect at any time, which removes the stored tokens immediately.

Outlook and Microsoft 365

Choose Outlook and sign in with Microsoft. The permissions and the disconnect behavior work the same way as Gmail.

SMTP

If your email is on another provider, connect it over SMTP. You will need the SMTP host, port, username, and password from your provider. SMTP is the most flexible option and works with most business email systems.

Daily limits and sending schedule

Every mailbox has a daily limit, which is the most emails it will send in one day, and a sending window, which is the hours and days it is allowed to send. Each mailbox runs on its own schedule and its own counter.

The daily limit protects your reputation. Sending thousands at once is the fastest way to land in spam.
The sending window keeps your email arriving during business hours, which looks natural and gets better engagement.
If you connect more than one mailbox, each one sends independently, so one being busy does not hold up another.

Start low, raise slowly

A new or lightly used mailbox should start with a low daily limit and increase it gradually over a few weeks. The Deliverability guide explains warm-up in detail.

Mailbox health

OSENBOLT shows a health status for each mailbox so you can tell at a glance whether it is sending normally. A healthy mailbox is sending within its limits with low bounces. A mailbox at risk usually has a high bounce rate or has been flagged, and it is worth pausing to clean your list before continuing.

Disconnecting a mailbox

You can disconnect a mailbox at any time from the Mailboxes page. Disconnecting removes the stored access tokens right away and stops any further sending from that account. Campaigns that were sending from it will have nothing to send through until you connect another mailbox and point them at it.