---
title: Connect your Microsoft 365 email to Infinity3
description: "Connect your Microsoft 365 email account to keep supported customer emails and replies together in Infinity3, alongside contact details, notes and tasks. Each team member connects their own email account through their own Infinity3 profile. #### Before you start You’ll…"
url: "https://www.infinity3.co.uk/help/connect-your-microsoft-365-email-to-infinity3/"
updated: "2026-10-07"
category: "Infinity3 Platform / Email & Conversations"
---

# Connect your Microsoft 365 email to Infinity3

Connect your Microsoft 365 email account to keep supported customer emails and replies together in Infinity3, alongside contact details, notes and tasks.

Each team member connects their own email account through their own Infinity3 profile.

#### Before you start

You’ll need:

- Access to your Infinity3 account.
- Your Microsoft 365 email login.
- Your phone or other authentication method if Microsoft asks you to verify your sign-in.

#### Connect your account

1. Log into the Infinity3 Platform at app.infinity3.ai.
2. Open **Settings** → **My Profile**.
3. Select **Email and conversations** in the left-hand sidebar.
4. Find **Email (2-way sync)**, select **Outlook**, then click **Connect**.
5. Sign into the Microsoft 365 account you want to connect.
6. Review and accept the requested permissions. The connection may be named **LeadConnector** on Microsoft’s permission screen.
7. Return to **Settings** → **My Profile** → **Email (2-way sync)** and check that your email address appears as connected.

If Microsoft displays “**Need admin approval**”, ask your Microsoft 365 administrator or IT provider to approve the connection.

#### How email sync works

Once connected, supported emails from customers already saved as Infinity3 contacts can appear in their conversation history.

You can reply through Outlook or Infinity3, and supported replies in the synced thread can appear in both places.

The connection starts syncing supported messages after setup. It does not import your previous email history.

#### Can colleagues see my customer emails?

Colleagues with permission to access the customer’s record and Conversations can see messages that have synced into Infinity3, including your replies.

For example, if a customer emails you and you reply in Outlook, a colleague with the appropriate access can open that customer’s conversation in Infinity3 and read the synced exchange.

This does not copy your messages into your colleague’s personal Outlook inbox.

#### What about new customers?

Email sync does not reliably capture every email involving someone who isn’t already an Infinity3 contact.

When starting an email in Outlook to a new contact, add the **Auto BCC address** shown in your Infinity3 email sync settings to the email’s BCC field. This can create their contact record and conversation so future supported messages can sync.

#### Check the connection

1. Use an external email address saved as an Infinity3 contact.
2. Send an individual email from Infinity3 using your connected Outlook address.
3. Reply from the external account.
4. Check that the exchange appears in Outlook and the contact’s Infinity3 conversation.

Use an external address for this test. Emails between team members who are also users in the same Infinity3 account do not sync.

#### Things to know

- Newsletters and automated emails use the platform’s separate email sending service.
- Attachments larger than **3 MB** can prevent a message from syncing.
- What colleagues can see depends on their Infinity3 permissions.

If your account shows as connected but the test messages don’t appear, contact Infinity3 with the affected email address and details of the test.