Integrate 100Hires with Gmail or Outlook

Connecting your mailbox to 100Hires lets you send candidate emails from your own address, keeps every reply on the candidate timeline, and threads conversations correctly. Without a connected mailbox you can still draft messages, but you cannot actually send them, and incoming replies will not be associated with the right candidate.

Why connect a mailbox

Without a connected mailbox you can compose drafts but cannot actually send them, replies from candidates do not appear on the timeline, and emails get associated with no thread. Once a mailbox is connected, 100Hires uses your address as the sender, captures replies into the candidate profile, and threads every message together.

What gets connected

• Sent and received emails on the candidate timeline.
• Attachments on both outgoing and inbound messages.
• Reply threading so the full conversation reads as one chain.
• Send-as identity so messages come from your address.

Connect Gmail (Google Workspace or personal)

1. Go to Settings > Integrations > Gmail.
2. Click Connect.
3. Sign in with your Google account and approve the OAuth consent screen. 100Hires requests Send and Read scope only.

If your team is on Google Workspace, connect the Workspace account rather than a personal Gmail so deliverability and domain reputation match the rest of your company email.

Connect Outlook (Microsoft 365)

1. Go to Settings > Integrations > Outlook.
2. Click Connect.
3. Sign in with your Microsoft 365 account and approve the OAuth consent screen. 100Hires requests Mail.Send and Mail.Read scope.

Daily sending limit

Every connected mailbox has a configurable daily send limit - click the pencil icon next to the mailbox on the Integrations page to edit it. The default is permissive so transactional emails are never blocked. If you plan to send cold outreach from the mailbox, lower the limit to around 50 per day to protect deliverability.

Connect multiple mailboxes

You can connect more than one mailbox and route volume sends through the Email Carousel. One mailbox stays as the default for transactional emails (interview invites, offers, system notifications), and the carousel rotates the others to spread cold-outreach volume across addresses.

Recommended setup for cold outreach

Brand-new mailboxes should not jump straight to 50 sends a day. Warm them up for 7 to 14 days at 5 to 10 sends per day before pushing volume through them. Add the new mailbox to the carousel during the warm-up window so it builds reputation gradually alongside your established sender.

Disconnect or re-authorize

If you see a "Mailbox not authorized" error, the OAuth token has expired (this happens after a password change, MFA reset, or a long period of inactivity). Open Settings > Integrations, disconnect the affected mailbox, then reconnect it through the OAuth flow to refresh the token. Sending resumes immediately.

Updated on: 15/06/2026