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# How to bulk connect Outlook/Office 365 accounts


# **User Guide — Connect Microsoft 365 Tenant to MailReach (Client Secret)**

This guide explains how to configure a Microsoft Entra ID (Azure AD) application so **MailReach** can connect to your Microsoft 365 tenant using:

✅ Application permissions
✅ Admin consent (one-time)
✅ Client Credentials (server-to-server)
✅ Client Secret authentication


## **Prerequisites**

You need:

* A Microsoft 365 tenant
* An admin account with permission to:
    * Register applications
    * Grant tenant-wide admin consent

Helpful reference on admin roles:
https://learn.microsoft.com/en-us/entra/identity/role-based-access-control/permissions-reference


# **Step 1 — Register the App in Entra ID**


1. Open Azure Portal: https://portal.azure.com
2. Go to: **Microsoft Entra ID → App registrations**: https://portal.azure.com/#view/Microsoft_AAD_IAM/ActiveDirectoryMenuBlade/~/RegisteredApps
3. Click **New registration**
4. Enter:
* **Name**: MailReach Outlook Connector (recommended)
* **Supported account types**: ✅ Single tenant
* **Redirect URI**: ❌ Leave blank (not required)
5. Click **Register**


✅ Copy and save these values (you’ll need them later):
* **Application (client) ID**
* **Directory (tenant) ID**

Docs:
https://learn.microsoft.com/en-us/entra/identity-platform/quickstart-register-app



# **Step 2 — Add Microsoft Graph Application Permissions**

1. Open your app → **API permissions**
2. Click **Add a permission**
3. Select **Microsoft Graph**
4. Select **Application permissions**

Add the permissions MailReach requires (typical email integration):

* Mail.ReadWrite *(or Mail.Read depending on your needs)*
* Mail.Send
* User.Read.All

⚠️ Make sure these are **Application permissions**, not Delegated permissions.

Docs:
https://learn.microsoft.com/en-us/graph/permissions-reference

# **Step 3 — Grant Admin Consent (One-Time)**

Go to **API permissions** and click:

✅ **Grant admin consent for (Your Tenant Name)**

After this, permissions should show:
✅ “Granted for (Your Tenant Name)”

Docs:
https://learn.microsoft.com/en-us/entra/identity-platform/v2-admin-consent

# **Step 4 — Create a Client Secret (IMPORTANT)**

1. In your app, go to **Certificates & secrets**
2. Under **Client secrets**, click **New client secret**
3. Enter:
* **Description**: MailReach secret
* **Expiration**: choose a suitable duration (e.g. 12 or 24 months depending on your policy)
4. Click **Add**


## **✅ Very Important: Save BOTH the Secret, the Secret Value and Expiration Date**

When the secret is created, you will see these fields:
* **Secret** ✅ (this is the actual client secret)
* **Secret Value** ✅ (this is the actual client secret value)
* **Expires** ✅ (expiration date)

⚠️ You must copy and store BOTH immediately.

### **You will need to copy/paste these into the MailReach Tenant Connection form:**

* **Tenant ID**
* **Client ID**
* **Client Secret (Value)**
* **Client Secret Expiration Date**

> Important: Microsoft only shows the **Secret Value once**.
> If you lose it, you must create a new secret.

Official docs:
https://learn.microsoft.com/en-us/entra/identity-platform/quickstart-register-app#add-a-client-secret

# **Step 5 — Enter Values in MailReach**

In the MailReach “Connect Microsoft Tenant” form, paste:

✅ **Directory (tenant) ID**
✅ **Application (client) ID**
✅ **Client Secret (Value)**
✅ **Client Secret Expiration Date**

This allows MailReach to authenticate and access the mailboxes approved by your tenant policies.