Migrating emails from the existing email service to Zoho Mail

Email Migration from current Email Service Providets to Zoho Mail Servers

Zoho Mail offers simple solution to migrate your email from your existing email service to the respective user accounts in Zoho Mail directly. IMAP Migration is the most recommended process to migrate the emails as the emails are migrated along with their folders and state details. The impact of the change in email service will be very minimal for the users, as they can continue from where they left. This also ensures that they easily gets accustomed to the new email service, without affecting the productivity. 

In case the previous email server does not support IMAP, then the emails can also be migrated via POP migration. 

If the previous email service was run by an inhouse/ on-premise Exchange Server (without POP/IMAP support) or the users emails were in Outlook and available as offline PST files, then the administrator can use Exchange Migration Wizard to migrate the emails from Exchange Server/ Outlook to the respective user accounts in Zoho Mail. The Zoho Mail Migration Wizard also supports Hosted Exchange Environments, to migrate the emails using Outlook Profile details, connecting to the Hosted Exchange server. 

Advantages of IMAP Migration over POP

If your emails are in a cloud hosted email service like Google Apps or Yahoo or any other cloud email server which support IMAP Access, you can perform a server to server migration via IMAP from the Control Panel. 

Zoho Mail supports both IMAP and POP Migration, but IMAP Migration has more advantages compared to the POP Migration.

IMAP MigratoinPOP Migration
Folder details are migrated.POP does not support Folder based migration. All emails are migrated to Inbox.
Email states (Read/ Unread) are maintained.The emails retrieved as 'Unread' via POP

Multiple Client support:

  • Emails are migrated even if accessed by other clients.
  • The emails are synced in multiple clients with state maintenance
  • The emails available in the source mailbox is synced along with folder and state information.
  • The emails sent by other clients are synced via IMAP.  

 

Only Single Client support:

  • If there are multiple client requests, the email is provided only to a single client.
  • The emails retrieved via POP already are not available for migration.
  • The emails sent by other clients will not be migrated, as it is not supported by POP Servers 

 

The migration is generally fast, and the migration info is detailed.The migration via POP is slower than IMAP Migration.
Specific failures in migration can be tracked and corrected.The failure information in POP is not specific and will be vague.

Details Required before Migration:

For both POP/ IMAP Migration, the follwing details are required. 

  • Name of the Server - Hostname of the IMAP Server or the POP Server from which the migration needs to initiated
  • Server Port - For source Server standard ports for SSL and Non SSL are supported. 
    • Supported ports for IMAP  - 143 (Non SSL), 993 (SSL) 
    • Supported ports for POP - 110 (Non SSL), 995 (SSL) 
  • SSL Type - Only Trusted Certificates are supported. Self Signed SSL certificates are not supported due to security reasons
  • Source User Names and Passwords for the user accounts - Make sure that the source accounts have IMAP access turned On. 
  • Exclude Folder List - The  administrator can exclude some folders like "Spam" to qiucken the migration process. Further they can ask the users to create a common folder and move the emails that need not be migrated. This folder can be provided in the common exclude list, which will apply for all users. 
  • 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 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. 
  • IMAP Path Prefix : Some IMAP server expect the PATH Prefix details for connecting and retrieving emails via IMAP. 
  • Black Out Time - In case there is any known down time for the server or particular times of the week during which the server is overloaded, specify the Day of the week, Time in 24 hour format (From 'x' hours to 'y' hours) and the corresponding Timezone. The migration would be paused during the specified time duration to avoid any migration failures due to that. The Blackout Time and Timezone are applicable, only if there are any predetermined Time Intervals, during which the migration should be paused. 

Source Server Details:

To add a new migration, you need to add the source server from which the emails should be migrated. You can also perform migration in batches, and also from different servers if you have multiple domains hosted with different providers and want to migrate everything to Zoho Mail. 

  1. Log in to https://www.zoho.com/mail
  2. Launch Control Panel » Mail Administration » Email Migration
  3. Select Add Migration, to provide server details for migration
  4. Provide a title for the migration
  5. Select the Migration Protocol as IMAP or POP based on your preference.
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  6. Provide the Host-Name of the server , the SSL type and the port number for migration. 
  7. Provide the maximum connection limit for your server.
  8. Exclude Folder ist - The list of folders that need not be migrated during the migration. 
  9. Select Add Migration to save the server details. 
  10. You will be taken back to the Migration Home page. 
  11. You need to add the account details to be migrated as the next step. 

Source User Account Details for Migration 

After you have added the Server details, you will be taken back the Migration Home page. Click the Migration, to add the source accounts to be migrated. 

You can add the accounts manually or import the details from a CSV file. However, make sure that you have the source and the destination account details ready. For each user added, the source credentials are checked with the server and the user gets added only if the source authentication is successful. 

Steps to add user accounts for Migration:

  1. Select the Migration Name to which you want to add the source and destination details. 
  2. Select Add Accounts to add the account details manually
  3. Provide the Source username/ Password and the Destination to which the emails should be migrated to. 
  4. In case of IMAP migration, you can choose to skip any folders during migration.  
  5. The skip folders will be handy when the admins rerun migrations for the same set of users for some new emails or missed emails. 
  6. This will be authenticated with the source server provided, once you click Add.

Steps to Import users from CSV file:

  1. Prepare an excel file or a Zoho Sheet with the headers Source, Password, Destination. You can optionally include a column Priority, which specifies the order in which users accounts needs to be migrated.
  2. Fill in the details under the respective columns for the user accounts to be migrated.
  3. Save the file as a CSV file.
  4. Click Upload Accounts link in the Migration Accounts page.
  5. Choose the respective file and Click Ok to upload the accounts.
  6. The accounts added will be listed in the section.
  7. You will be able to modify the Server details or the Migration type, before you start the migration. 
  8. Check whether all the Accounts to be migrated has been listed in Accounts section.

Authentication Errors:

  • Make sure that the user has not changed the password of the source account when you run the migration. 
  • The access to the old server is still in place for the account, until the migration is completed. 
  • In case you are migrating from Google Apps servers, you may require to login via Web once to authenticate the IMAP activity in your account. In this case, request the user to login to the Google Apps account from web and follow the steps listed in this help page for the error 'Web login required': https://support.google.com/mail/answer/78754
  • Similarly, even in Outlook.com, your source account access may be blocked on detection of activity from new IP Addresses. We request you to login and allow access to the Zoho Mail IP addresses, listed there under Recent Activity. Select 'This was me' to trust the Zoho Mail IP addresses and proceed with the migration.

Start Migration Process

In the Control Panel, navigate to Migration under Mail Administration. 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.You can add multiple migrations from different servers or from the same server for different sets of users to have a phased and planned migration. 

  1. The list of migrations you have added will be listed in the Migrations page.
  2. Click 'Start' link, across the migration you have just added to start the migration. 
  3. The Migration will be scheduled and the status will be 'In Progress' for the migration that is currently running. 
  4. You can view the overall migration status in the listing, and detailed migration status in the Accounts section. 
  5. For IMAP Migration, detailed statistics along with folder information will be available. 
  6. Click the 'Total' link to view the detailed information about the folder-wise migration details.
     
  7. Under each account, the errors, if any, will also be listed with details. Click Failed to view the number of emails not migrated and the reason.
    The common reasons include: 
    • Email Size Exceeded  - If the size of the email in the source server exceeds the maximum size defined in the users email policy, such emails will not be migrated. 
    • Mail already present - Duplicate - If the email is a duplicate of an email already in the users account in Zoho, the duplicate emails will not be migrated.
    • Too many addresses - If the email has the number of To addresses which exceeds the allowed limit in Zoho Mail, those emails will not be migrated. 
    • Invalid Message  - If the email format is not as per the RFC defenitions, with incorrect header or email format, such emails will not be migrated.
    • Unable to Process - In case there are any internal processing errors during the migration of a particular email, such emails will be skipped during migration.
  8. Apart from the migration statistics, the administrator and the users will receive a summary of migration information after the completion.

In case of some failures like Internal Error, the administrator can migrate only selective folders instead of entire migration. This will optimize the run time for the migration, by removing the duplicates and the check for duplicate emails.