IMAP Migration from Microsoft 365 to Zoho Mail

If your organization's email was hosted with Microsoft 365, you can migrate your email data easily via one-click migration. Alternatively, you can also choose the IMAP migration method to transfer the data from your Microsoft 365 accounts to the corresponding accounts in Zoho Mail. Ensure that user accounts are created in Zoho Mail before adding the migration. Refer to our help page for detailed instructions to add users in Zoho Mail.

Prerequisites

Ensure you have the below data available before you start the IMAP migration:

• User Accounts - Create the necessary user accounts in Zoho Mail.
• Server Port - Zoho Mail supports SSL and Non-SSL server ports for IMAP. 
  • SSL - 993
  • Non-SSL - 143
• SSL Type - Only Trusted Certificates are supported. Self Signed SSL certificates are not supported due to security reasons. 
• Maximum Connection Limit - The maximum connection limit is the number of maximum connections accepted by the server at a given time. For example, if you provide 5 as the maximum connection limit when the migration is started, the migration process will be started simultaneously for 5 users. The migration process will be faster when there are parallel migrations happening between the servers. 
• Path Prefix - Some IMAP servers expect the PATH Prefix details for connecting and retrieving emails via IMAP. 

Create a New IMAP Migration

To create a new IMAP migration, follow these steps:

1. Log in to Zoho Mail Admin Console and choose Data Migration from the left pane.
2. Click Start data migration for the first migration or click Create for subsequent migrations.
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3. The data migration process involves three simple steps that follow:
   • Add server details
   • Add server settings
   • Create​ migration

Add Server Details

Follow these steps to add source server details:

1. Enter the migration name for the server configuration.
2. Select Add new server details in the Select saved server details drop-down.
3. Choose IMAP in the Select Protocol/Application drop-down.
   
4. In the additional options that appear, make the selection as given below to add source server details:
   1. Choose Others option under Source server type - Others.
   2. Add outlook.office365.com in the Source server address.
   3. You can either choose SSL (Port Number - 993) or None (Port Number - 143) under Security.
   4. Enter the Path Prefix, if your source server mandates it.
   5. If you wish to bypass the SSL certificate check, select Skip certificate check and click Add.
      The server Settings page appears.
      

Add Server Settings

On the Settings page, enter the values for the fields that follow:

1. Enter a name for the server settings.
2. Under Folders to migrate, you can choose either the All folders or Specific folders option.
3. If you choose the All folders option, you can choose to skip any folders during migration using the Exclude Folder List option.
4. The skip folders option will be handy when the admin reruns migrations for the same set of users for some new emails or missed emails. Enter the names of the folders within double quotes ("Folder1"), in which case only that folder will be excluded. If you want all subfolders under a parent folder to be migrated enter the folder name followed by /* within double quotes ("Folder1/*"). For detailed information on the convention, refer here.
5. If you choose the Specific folder option, you can specify the folders that need to be included in the Include Folder List.
6. In the Include Folder List, enter the names of the folders within double quotes ("Folder1"), in which case only that folder will be included. If you want all subfolders under a parent folder to be migrated enter the folder name followed by /* within double quotes ("Folder1/*"). For detailed information on the convention, refer here.
7. Under Emails to migrate, select whether you want to migrate all the emails or the emails that you have received after a specific date.
8. In Enable POP access for the migrated emails, select Yes if you want your users to view the migrated emails when the account is configured as POP in other email clients. Otherwise, select No.
9. Click Add and proceed to the CREATE migration step.
   You have now successfully configured your server settings.
10. If you have enabled multiple authentication methods, select one of the Preferred Authentication Type that suits your organization's needs:​
    • Enter user password manually
    • Each user supplies their password
    • Authenticate using individual user's OAuth

    Note:

    • The Preferred Authentication Type options will be rolled out in a phased manner and be available only to the organizations who have availed of one of our paid plans.
    • If you want the option enabled for your organization, please reach out to us at support@zohomail.com.

​Enter user password manually

This is the default authentication type that you were using before introducing the Preferred Authentication Type feature. If you want to migrate data using this method, click Add and proceed to the Create migration step.

At the time of user addition, admins must enter the user's Source email address, user's Source password and then select the Destination email address.

Each user supplies their password

Each user supplies their password authentication does not require any action from the admin at the time of server settings configuration. If you want to migrate data using this method, simply click Add and proceed to the Create migration step.

When you add a user, an auto-generated email will be sent to the user's source account. The users must open the link from the email and enter their password. The user entered password is encrypted and the admin will not be able to see the actual password.

The Password Supplied column in the Users page will indicate No till the time a user provides his/her password. Once the user provides the password, the Password Supplied field changes to Yes.

Authenticate using individual user's OAuth

If you select the preferred authentication type as Authenticate using individual user's OAuth, you must share the Authentication URL with each user through an email or other means. Below are the steps involved in Authenticate using individual user's OAuth:

1. Share the Authentication URL that appears on the SETTINGS page with all the users for whom you require data migration.
2. The user should do the steps that follow:
   1. Log in to Zoho Mail with their credentials.
   2. Open the Authentication URL shared by the admin. Office365 login page appears.
   3. Enter their source email address and validate it with their password. A Successfully verified message appears.
   4. Share the authentication completion with the administrator.
3. Once the user completes the authentication steps, click Add and proceed to Create migration step.
   You have completed the server Settings configuration for the Authenticate using individual user's OAuth method

Create Migration

Follow these steps on the Create migration page:

1. Enter a Maximum Connection Limit and select when you would like to pause the migration when the storage reaches 80% or 95%.
2. Click Create and then proceed to the user addition page.

Add User Accounts

Zoho Mail provides two options to add user accounts for migration such as:

• Manual user addition
• Add bulk user accounts through the CSV option

Manual User Addition

The user addition step differs based on the authentication type that you select. Follow one of the below procedures as per your requirement:

• Enter user password manually
• Each user supplies their password
• Authentication using individual user's OAuth

Enter User Password Manually

1. From the Migration list, select the migration to which you want to add users.
2. Navigate to the Users tab and click Add.
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3. Enter the Source user name, Source password and Select the destination email address.
4. Choose the priority for the migration and click Add. The user gets added successfully. Proceed to the Start Migration step.
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Each User Supply Password

1. From the Migration list, select the migration to which you want to add users.
2. Navigate to the Users tab and click Add.
   
3. Enter the Source user name and Select the destination email address. An auto-generated email is sent to the user's source account to request their password.
4. A Password Supplied column displays whether the user had provided their password or not.
5. Choose the priority for the migration and click Add. The user gets added successfully. Proceed to the Start Migration step.

Authentication Using Individual User's OAuth

1. From the Migration list, select the migration to which you want to add users.
2. Navigate to the Users tab and click Add.
   
3. Make sure that the source and destination account validation is done by each user with the Authentication URL provided by the admin.
4. Enter the Source user name and Select the destination email address.
5. Choose the priority for the migration and click Add. The user gets added successfully. Proceed to the Start Migration step.

Steps to Import users from CSV file

Instead of manually adding the users for migration, you can also add the user details to an excel sheet, save it as a CSV file and upload it. The user accounts mentioned in the CSV will be uploaded for migration.

1. From the Migration list, select the migration to which you want to add the source and destination user account details. 
2. Navigate to the Users tab.
3. Click Import to upload the user accounts using a CSV file.
   
4. The format for entering the User Details in the CSV file can be found in the sample file attached in the popup.
5. Once you have prepared your CSV file, click Browse Files, and choose the CSV file that you would like to import.
6. A preview of all the users in the CSV file, along with details about whether they were imported or not will be shown on screen.

Start Migration

Once you have added the user accounts for the migration, you can start the migration. Ensure that the source passwords are not changed after adding the users for migration. The password should be the same until the entire migration process is completed.

1. Click the Start Migration button after adding the users. If you have navigated out of the page where you added the users, select the migration that you want to start from this page, and click Start Migration.

   Note:

   Below are a few exceptions for the Each user supplies their password authentication type:

   • The Password Supplied column must be Yes before you click Start Migration.
   • If the Password Supplied column displays No, it means that the user did not provide their password. Hover over the respective user and click the Resend button to send an email once again.
   • If the migration fails, one of the reasons could be password validation failure. In such cases, you must follow these steps and add a new migration. When you add the user, the Password Supplied column will display Yes. Hover over the user and click the Reconfirm button to send an email once again to the corresponding user.
2. You can view the progress and statistics regarding the migration on the same page.
3. Detailed statistics regarding each user's migration can be viewed by clicking on their email address in the migration progress page.​
4. For mail migration, detailed reports along with folder information will be available.
5. Click Mail Failures to view the detailed information about the folder-wise migration details.
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For more information on reasons for migration failure, follow this help page.