Comcast Email to Office 365 Migration

• Moving important email from an ISP-associated mailbox to Microsoft 365 can reduce long-term dependency on the source service and place business communication under centralized Microsoft 365 administration.
• Microsoft 365 is an all-in-one productivity suite that combines email, Office apps, collaboration, and cloud storage under a single platform.
• You can easily integrate Outlook, Teams, SharePoint, and OneDrive to access everything in one place, improving productivity and communication.
• No need for external hosting or domains. Office 365 is a complete cloud-based email solution managed directly by Microsoft.
• Easy email management. You can add public folders, shared mailboxes, and aliases quickly through the Microsoft 365 admin center.
• Enterprise-grade security and reliability. Your data and emails are stored safely on Microsoft’s secure cloud servers with high uptime and compliance.

Before you start the Comcast-to-Office 365 migration, create a detailed plan covering source access, target readiness, scope, validation, and cutover. Planning helps reduce avoidable migration risk and gives an overview of the operation. Here is a checklist of points to consider.

1. Confirm that each Comcast/Xfinity mailbox can sign in successfully and that third-party email-program access is enabled in Xfinity Email security settings. Prepare the Microsoft 365 account with the permissions required by the selected EdbMails target connection.
2. Keep your Comcast email's IMAP connection information handy if you have an IMAP server on the source.
3. Make a list of what you want to migrate and what you want to leave behind.
4. Remove unwanted and unnecessary mailboxes from the source.
5. Request that your users save or export large attachments to their local storage.
6. Decide which Microsoft 365 email address or custom domain you will use after migration. If the source address is an @comcast.net address, the comcast.net domain itself cannot be repointed to your Microsoft 365 tenant.
7. Communicate all of these changes to your end users, stakeholders and keep them updated.
8. Perform a pilot migration to ensure everything works as expected.
9. After you complete the migration, allow enough time for testing and verification.
10. Add the MX records on Office 365 and configure Outlook for all users.

1. Create a list of users in a CSV file, which you want to migrate from Comcast.
2. Find the name of your source email server from an email client
3. Purchase a suitable Office 365 licensing plan. You can also sign up for a 30 day free trial and decide to go with a suitable one later. Compare Office 365 business plans and Compare Office 365 enterprise plans
4. Create Office 365 mailboxes and assign licenses to them
    Add users and assign licenses to Office 365 users
    Assign Microsoft 365 licenses to user accounts
5. If you plan to migrate your mailboxes to Office 365 Public folders, ensure that you create and configure the Public folder mailboxes on the target server.
    Create Office 365 Public folder and assign mailbox user.
6. Similarly, if you want to migrate mailboxes to Office 365 In-Place archive, enable them from the admin center.
    Steps to enable archive mailbox in Microsoft 365.
7. If you have a custom email domain from the source which you want to retain and receive emails to, you must add and verify the domain on Office 365.
    Steps to add a custom domain to Office 365 and steps to add DNS records to connect your domain.
8. Configure Office 365 to send and receive large messages.
    Follow the steps to increase the message size on Office 365 to 150MB. See message size limits on Office 365 for more information.

• Step 1: Download and Install EdbMails software

  • Download and install EdbMails on your computer.

    

  • Launch the EdbMails application on your computer.
  • Enter your registered email address and password, then click ‘Login’. If you’re using EdbMails for the first time, select ‘Start Your Free Trial’ to continue with the trial version.
    Note: The trial version includes all major features and lets you migrate up to 30 items per folder. To migrate all eligible items for licensed mailboxes, purchase the required IMAP Migration license from the official EdbMails website.

     Click here to view IMAP Migration pricing details.

    Once the purchase is complete, close and reopen the application. Log in again with the same email address and password used during the purchase to activate your license successfully.

    

  • Select the option ‘IMAP (Gmail, Outlook & more) Migration’.

    

  • Select ‘IMAP to Office 365 Migration’.

    

  • You can either go with the default job name or click on 'New Job' if you'd like to customize it.

    

• Step 2: Connect to the Source Comcast Mail Server

  • To migrate a single Comcast email account, select ‘Single User / Account Migration’, then choose the appropriate connection method such as ‘Connect to IMAP Server’ or ‘Connect to POP3 Server’ based on your setup.
  • After selecting the option, click ‘Next’ to continue setting up the connection.

    

  • Use imap.comcast.net as the incoming IMAP server with port 993 and SSL/TLS. Confirm that Xfinity third-party email-program access is enabled for the mailbox.
  • Enter the full Comcast.net email address and the current mailbox credential required for the source connection.
  • Next, click the ‘Login’ button.

    

  • For migrating multiple Comcast mailboxes in a single operation, choose ‘Multiple (Bulk) Users/Accounts Migration’ and select the appropriate connection option such as ‘Connect to IMAP Server’ or ‘Connect to POP3 Server’, then click ‘Next’ to continue.

    

  • Click ‘IMAP Migration CSV File’.

    

  • Open the CSV file and input the required details, such as email address, password, server name, and port number. Once you've entered all the information, save the file.

    

  • After updating the CSV file, save it and close it.
  • Next, click the 'Load Modified CSV File' button, locate your updated CSV file, select it, and open it to proceed.

    

• Step 3: Select source Comcast server mailboxes

  • Choose the mailboxes or specific folders you wish to migrate, then click ‘Next’ to continue.

    

• Step 4: Connect to target Office 365 server

  • Select the ‘Add New Connection’ option to establish a connection with your target Office 365 account.
  • If you have previously set up a connection, you can choose it from the available list and click ‘Connect to Existing’ to proceed.

    

  • Choose the necessary connection options and click ‘Next’ to continue

    

  • Select any of the available options to establish a secure connection using OAuth 2.0 modern authentication.
  • Choose Auto Registration for a quick and straightforward setup. Sign in with a Global Admin account and grant the required permissions to automatically register the application in Azure AD.
  • Alternatively, select Manual Registration if you prefer to enter the Azure AD application details yourself. This method supports both Global Admin accounts and accounts with Full Access permissions.
  • Click ‘Login’ to proceed.

    

  • Authenticate on Microsoft sign-in page.

    

  • After successful authentication, choose one of the following options to load the mailboxes:
    • i) Load Mailboxes Automatically: After signing in, EdbMails automatically retrieves and displays the mailboxes, making the process quick and straightforward. If the automatic mailbox list does not return every required target, use the alternative CSV-loading option below and verify the destination mailbox list before continuing.
    • ii) Load Mailboxes using CSV file: If all mailbox names are not retrieved through the automatic method, select the ‘Load Mailboxes using .CSV file’ option to manually add and load the required mailboxes.
    • iii) Load Mailboxes from previous list: This option allows you to load mailboxes directly from the list that was previously imported and saved in your earlier session.
  • Choose ‘Load Mailboxes Automatically’ and click ‘Next’ to continue.

    

• Step 5: Comcast to Office 365 mailboxes mapping

  • Select a preferred option to map the source mailboxes and folders with their corresponding mailboxes and folders on the target Office 365 account.

    

  • EdbMails lets you automatically create the required mailboxes in your target Office 365 account.
  • It also automatically maps your source Comcast mailboxes and folders to the matching ones in Office 365, making large migrations easier to manage.

    

• Step 6: Start Comcast to Office 365 migration

  • Verify the mailbox mapping, then click the ‘Start Migration’ button to begin the migration process.

    

  • Click the ‘View Logs’ button to access the full migration report. The report provides detailed information, including the mailbox mapping, an overall summary of the migration, and the item count for each mailbox and folder that was migrated.

    

• Step 1: Configure mail flow for the address you will use in Microsoft 365

  If you are migrating a custom domain that you control, update its Microsoft 365 DNS and MX records after the migration is validated. For an @comcast.net source address, you cannot change the comcast.net MX record; use the Microsoft 365 address or a custom domain that you own for new mail delivery.

• Step 2: Set up a new Outlook profile for users in the new domain

  If users experience issues connecting to Office 365 mailboxes, create and configure a new Outlook profile for each user in your domain.

  For troubleshooting, explore our knowledge base articles. If you need further help, browse the FAQs or reach out to our support team for tailored assistance.