Microsoft 365 integration

Operate cold-email campaigns through connected Microsoft 365 inboxes.

Authorize Microsoft mailbox synchronization, verify SMTP sending independently, rotate eligible business inboxes under enforced limits, and manage replies in the MailSequence unified inbox.

Microsoft Graph mailbox sync·Independent SMTP test·Reply synchronization

Connection flow

Authorize the mailbox, then verify sending readiness.

Prepare the domain

Add an owned sending domain and complete the supported authentication path before campaign launch.

Create the inbox record

Choose Microsoft 365, identify the business mailbox, and provide the sending settings required by the connection flow.

Authorize Microsoft access

The OAuth flow requests Microsoft Graph mail read, mail read/write, and offline access for ongoing synchronization.

Test SMTP readiness

MailSequence checks the outbound transport separately. Failed SMTP testing leaves the inbox visible but ineligible to send.

Add it to a pool

Select the connected, send-ready inbox for campaign rotation under inbox and domain capacity.

Synchronize replies

Fetch newer Microsoft threads and messages, then search, assign, tag, and reply through the workspace inbox.

What authorization does

Use Graph for mailbox context and a tested path for outbound sending.

Microsoft authorization gives MailSequence the mailbox access needed to synchronize conversations and state. The SMTP test remains an independent gate for sending eligibility.

  • Mail.Read for synchronized conversations
  • Mail.ReadWrite for mailbox-state operations
  • Offline access for refreshable authorization
  • Independent SMTP credential and connection test
Inbox readinessTwo checks
Microsoft authorizationMailbox sync
Refresh accessStored securely
SMTP testOutbound path
Both readyPool eligible

Operating controls

Keep Microsoft inboxes inside the same controlled workflow.

Domain readiness

Use the Cloudflare delegation path to prepare SPF, DKIM, and DMARC, then verify the resulting records independently.

Explore domain setup →

Capacity and rotation

Distribute sending across eligible inboxes while enforcing inbox and domain caps that rotation cannot bypass.

Explore controls →

Replies and reporting

Stop follow-up on associated replies and review delivery, responses, bounces, warmup, and health.

Explore reporting →

Provider documentation: Microsoft Graph's permission reference states that Mail.ReadWrite does not include permission to send, while Microsoft's SMTP AUTH guidance documents the separate outbound protocol.

FAQ

Frequently asked questions

Does Microsoft OAuth send campaign emails?

OAuth authorizes Microsoft mailbox synchronization. MailSequence tests the SMTP sending path independently and does not make the inbox campaign-eligible if that test fails.

Which Microsoft permissions are requested?

The connection requests Mail.Read, Mail.ReadWrite, and offline_access. These support conversation synchronization, mailbox-state operations, and refreshable authorization.

Can I connect a personal Outlook account?

MailSequence is positioned for business inboxes on owned domains. Use Microsoft 365 infrastructure appropriate for legitimate business outreach and provider policy.

Can I provision a Microsoft business inbox in MailSequence?

Yes. Configured Microsoft business inboxes can be provisioned after the domain is ready. Your plan includes its listed inbox allowance. Additional inboxes cost extra.

Does connecting Microsoft remove provider limits?

No. Microsoft policies and account limits still apply, and MailSequence adds inbox, domain, plan, warmup, and health controls.

What happens when Microsoft authorization expires or synchronization fails?

The inbox records authorization and synchronization errors for operator review. Disconnected or non-send-ready inboxes are excluded from campaign-pool eligibility.

Connect Microsoft 365 with both sync and sending checks visible.

Prepare the domain, authorize the mailbox, verify SMTP readiness, and add only eligible inboxes to campaigns.