Zimbra to Microsoft 365 Migration Guide
This guide explains how to migrate Zimbra mailboxes, contacts, and calendars to Microsoft 365 or Google Workspace using the Cloudiway SaaS platform.
Overview
The Cloudiway migration platform supports Zimbra server migration to Microsoft 365 or Google Workspace. This is a SaaS platform that connects directly to your Zimbra server - no on-premises agent is required.
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View Solution PagePrerequisites
To perform the Zimbra to Microsoft 365 migration, your Zimbra server must be accessible from the Cloudiway SaaS platform. The following ports must be open:
| Port | Protocol | Purpose |
|---|---|---|
| 143 | IMAP | Standard IMAP port for email migration |
| 993 | IMAP over SSL | Secure IMAP port for email migration |
| 7071 | HTTPS | Zimbra Admin port (default) |
| 443 | HTTPS | Zimbra web services (for contacts/calendars) |
What is Migrated
Cloudiway migrates emails using IMAP protocol. Contacts and calendars are migrated using native Zimbra APIs for full fidelity:
Migration Modes
Cloudiway supports two migration modes for Zimbra:
Step 1: Create Zimbra Connector
Create a Zimbra connector in the Cloudiway platform to connect to your Zimbra server:
Create New Connector
Go to Connectors > New and select Zimbra as the connector type. Select Mail as the product to migrate.
Configure Connector Settings
Configure your Zimbra server connection with the following parameters:
Administration Settings
| Parameter | Description |
|---|---|
| Administration Server Name* | The hostname or IP address of your Zimbra administration server |
| Administration Server Port* | The admin port for Zimbra administration API (default: 7071) |
| Use Administration ServerName for Zimbra Calls | Enable if the admin server should be used for all API calls |
Server Settings
| Parameter | Description |
|---|---|
| Domain Names | The email domains hosted on your Zimbra server (e.g., company.com) |
| Server Name* | The IMAP server hostname (usually the same as the admin server) |
| Server Port* | The IMAP port: 993 (SSL) or 143 (standard) |
| Ignore Mount Point Errors | When enabled, mount point errors will be ignored during migration. Keep disabled unless you experience issues with shared folders. |
Authentication Settings
| Parameter | Description |
|---|---|
| Administrator Account* | The Zimbra administrator email address with delegated access to all mailboxes |
| Administrator Password | The password for the administrator account |
| Authentication Mode | Select None for admin-based authentication, or choose another method if required |
Complete Setup
Click NEXT to review your configuration, then click NEXT again to save your connector.
LoginAsAdmin rights to access all user mailboxes. Without these permissions, you will get "Failed To Authenticate" errors.
Step 2: Create Target Connector
Create a target connector for your destination platform. You can migrate Zimbra to Microsoft 365, Google Workspace, or Exchange On-Premises.
Option A: Microsoft 365 Target
Create New Connector
Go to Connectors > New, select Microsoft 365 as connector type.
Configure Authentication
Choose Automatic mode and enter your Microsoft 365 Global Administrator credentials, then click GRANT ADMIN CONSENT.
Complete Setup
Review settings and complete the connector creation.
Option B: Google Workspace Target
Create New Connector
Go to Connectors > New, select Google Workspace as connector type.
Configure Service Account
Choose Automatic mode and sign in with your Google Workspace Super Admin account to authorize access.
Enable Domain-Wide Delegation
Follow the prompts to enable domain-wide delegation for the Cloudiway service account in your Google Admin Console.
Complete Setup
Review settings and complete the connector creation.
Option C: Exchange On-Premises Target
You can also migrate Zimbra to an on-premises Exchange server using EWS (Exchange Web Services).
Create New Connector
Go to Connectors > New, select Exchange On Premises as connector type.
Enter EWS URL
Enter your Exchange Web Services endpoint URL: https://your-exchange-server/EWS/Exchange.asmx
Select Authentication Mode
Choose your authentication method:
- Impersonation: Migration account impersonates each user (requires ApplicationImpersonation role)
- Delegation: Migration account has Full Access rights to each mailbox
- Self Service: Each user provides their own credentials
Complete Setup
Enter the migration account credentials and complete the connector creation.
Step 3: Configure Global Settings
Navigate to Mails > Global Settings to configure your migration options:
Migration Scope
| Setting | Description |
|---|---|
| Migrate Emails | Enable to migrate email messages from Zimbra mailboxes via IMAP |
| Migrate Calendar | Enable to migrate calendar events, appointments, and recurring meetings |
| Migrate Contacts | Enable to migrate contacts from Zimbra address books |
| Migrate Tasks | Enable to migrate tasks (if supported by target) |
Advanced Settings
| Setting | Description |
|---|---|
| Date Filter | Optionally filter items by date range to migrate only recent data |
| Convert Email Address | Rewrites email addresses found in headers and calendar items from old domain to new domain |
Step 4: Run Migration
Now you can populate the user list and run the migration.
Populate User List
Navigate to Mails > User List to add users for migration. There are three ways to populate the user list:
Option 1: Discovery (Get List)
Under MIGRATION, click on the Get List option:
Specify the following parameters:
Source Pool
Select the Zimbra source connector you created earlier.
Target Pool
Select the Microsoft 365 or Google Workspace target connector.
Matching Rule
Choose how source emails should be mapped to target emails:
- Mail Exact Match: source email = target email
- Keep Email Prefix Same as Source: only the domain changes
- FirstName.LastName: (e.g., [email protected])
Target Domain
Specify the target domain for the migrated users.
Option 2: Import User List
Click on MANAGE > Import to upload a CSV file containing the users to migrate.
CSV File
Click on BROWSE to select your CSV file. You can click Download sample csv to get a template file.
Source Connectors Pool
Select the Zimbra source connector.
Target Connectors Pool
Select the target connector (Microsoft 365 or Google Workspace).
Option 3: Create Manual Entry
Click on MANAGE > Create to manually add individual users. Enter the source Zimbra email address and the target email address for each user.
Run Audit (Recommended)
Before migrating, run an Audit task to assess mailbox sizes and identify potential issues:
Select Users
Select the users you want to audit using the checkboxes.
Start Audit
Click MIGRATION > Audit to start the audit process.
Review Results
Check the audit results to see mailbox sizes, item counts, and any errors.
Execute Migration
Once you have reviewed the audit results, you can start the migration:
Select Users or Batches
Select the users you want to migrate. You can migrate all users at once or create batches for phased migration.
Start Migration
Click MIGRATION > Start to begin the migration process.
Monitor Progress
Monitor the migration progress in the dashboard. You can see the status of each user and any errors that occur.
Delta Migration (Optional)
Run a delta migration to sync any new items created since the initial migration. Click MIGRATION > Start again to perform incremental sync.
Frequently Asked Questions
What ports does Cloudiway use to connect to Zimbra?
Cloudiway uses IMAP ports 143 (standard) or 993 (SSL) for email migration, port 7071 for Zimbra admin API, and port 443 for web services (contacts and calendars).
Can I migrate from hosted Zimbra without admin access?
Yes, Cloudiway supports self-service migration mode for hosted Zimbra. Each user receives an email with a migration link and provides their own credentials.
What if I get "Failed To Authenticate" error?
The admin account configured in your source connector doesn't have enough permissions. It should be granted LoginAsAdmin rights to access users' mailboxes.
What if I get "No Connection" error?
The Zimbra server blocked the connection. Check your firewall settings, server security restrictions, or IP whitelisting configuration.
What if I get "Request Not Allowed On Port" error?
The port configured in the platform is incorrect. Make sure you're using port 143 or 993 for IMAP and restart your migration.
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