IceWarp to Office 365 Email Migration

Migrate IceWarp email to Microsoft 365 when your organization is moving its mailboxes to Exchange Online. This EdbMails workflow uses IMAP for the source mailbox data, so the standard scope is email messages, attachments, mail folders, folder hierarchy, and common message properties exposed by IceWarp.

The EdbMails IMAP Migration Tool supports single and bulk mailbox connection, mapping, filters, concurrent processing, incremental follow-up runs, and reports. IceWarp documents secure IMAP on port 993 with direct TLS; port 143 can use STARTTLS, while unencrypted IMAP is not recommended.

Use this provider-specific guide together with the main IMAP to Office 365 migration page. Standard IMAP does not migrate contacts, calendars, tasks, rules, or other IceWarp collaboration data, so plan those workloads separately if required.

1. What Makes Microsoft 365 a Better Choice than IceWarp Server?

   1. App Integration: Microsoft 365 integrates seamlessly with Office apps like Word, Excel, PowerPoint, Teams, OneDrive, and SharePoint. For a smooth transition of data and collaboration tools when migrating from IceWarp, EdbMails offers a secure and efficient solution to transfer emails, and folders to Microsoft 365 with post-migration verification.
   2. Instant Collaboration: Microsoft 365 supports real-time collaboration through Microsoft Teams and cloud-based document editing. This IMAP workflow migrates supported IceWarp email data; calendars, contacts, tasks, rules, and other collaboration workloads require separate handling.
   3. Built-in Security: With enterprise-grade security, Microsoft 365 includes encryption, multi-factor authentication (MFA), and compliance with international standards like GDPR, HIPAA, and ISO, protecting sensitive business information.
   4. Business Scalability: The platform easily scales for businesses of any size, offering flexible resource management and high performance that grows with your organization.
   5. Data Safeguarding: Microsoft 365 includes tools like OneDrive for Business and Exchange Online Archiving for data backup and recovery.
   6. Service Reliability: Leverages a vast global data center network to provide consistent, reliable service with 99.9% uptime SLAs.
   7. Modern Productivity Tools: Regular feature updates, AI-powered tools, and continuous integration of new productivity applications keep businesses competitive and adaptable​.

2. IceWarp to Office 365 Migration Considerations

   1. IMAP data scope: Email and mail folders are available through standard IMAP; calendars, contacts, tasks, rules, and other groupware data require a separate workflow.
   2. Mailbox mapping: Large projects need verified source-to-target mappings, especially where user addresses change.
   3. Folder mapping: Review source folder names and target folder destinations before migration.
   4. Large mailboxes and attachments: Throughput depends on mailbox size, attachment sizes, server limits, bandwidth, and target throttling.
   5. Connection limits: IceWarp and firewall/session limits can affect concurrent migration.
   6. Cutover: MX/DNS and client changes should be performed only after target verification.
   7. Verification: Migration reports and target-side checks are required before the source is decommissioned.

3. Use EdbMails for IceWarp to Office 365 Email Migration

   EdbMails provides a guided IMAP-to-Microsoft 365 workflow for IceWarp email. Administrators can connect single or multiple mailboxes, review mapping, choose folders, apply supported filters, run concurrent migration, perform incremental follow-up passes, and verify results through reports.

   The Microsoft 365 target connection uses the current EdbMails OAuth-based authentication workflow. Source IceWarp authentication depends on the server configuration and organization policy.

4. IceWarp to Office 365 Migration Planning

   Planning is an important step before starting your IceWarp to Office 365 migration. Setting up the environment properly in advance helps reduce risks and prevent data loss. Below is a checklist of key points to consider before beginning the migration.

   • Determine the size of the data and number of mailboxes you want to migrate.
   • Make a list of all the data and permissions from IceWarp that you want to transfer.
   • Create appropriate user mailboxes on Office 365 and assign licenses to them.
   • Ensure you have enough network capacity and bandwidth to migrate.
   • Communicate the migration plan and flow to your end users.

5. IceWarp to Office 365 migration prerequisites

   IceWarp source

   • Confirm the IceWarp IMAP host name and authentication credentials.
   • Prefer the secure IMAP endpoint. IceWarp documents IMAP over SSL/TLS on port 993; port 143 can use STARTTLS, while unencrypted IMAP is not recommended.
   • For bulk projects, prepare the EdbMails sample CSV and test a small set first.
   • Check IceWarp connection/session limits, mailbox quotas, message sizes, and network access from the migration computer.

   Microsoft 365 target

   • Create/provision the required target mailboxes and assign licenses.
   • Add and verify the custom domain if it will be used for production mail after cutover.
   • Use the current EdbMails OAuth-based Microsoft 365 connection / app-registration workflow. Do not use retired Exchange Online ApplicationImpersonation guidance as a current prerequisite.
   • Review Microsoft 365 throttling and message-size limits.
   • Run a pilot mailbox and verify the target before scaling the migration.

6. Steps to Migrate IceWarp to Office 365

   • Step 1: Download and install EdbMails IMAP migration software setup

     • Download EdbMails and install the EdbMails software on your computer.

       

     • Start the EdbMails application on your computer.
     • Provide your registered email address and password, then click ‘Login’. If you are new to EdbMails, select ‘Start Your Free Trial’ to continue with the trial edition.
       Note: The trial lets you evaluate the workflow and migrate up to 30 items from each folder. To migrate all eligible items for licensed mailboxes, purchase the required IMAP migration license.

       View current IMAP migration pricing.

        See a detailed list of EdbMails system requirements for IMAP migration.

       

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

       

     • Select ‘IMAP to Office 365 Migration’

       

     • By default, the software creates a job name automatically. If required, you can select ‘New Job’ to provide your own custom name that is meaningful, distinct, and easy to recognize according to your requirements.
     • Click ‘Next’ to continue.

       

   • To migrate a single IceWarp mailbox, select ‘Single User / Account Migration’, choose ‘Connect to IMAP Server’, and click ‘Next’.

     

   • Choose the required method to load target Microsoft 365 mailboxes. If the automatic list does not include every required mailbox, use the supported CSV-loading option and verify the list before continuing.
   • Where supported and selected, EdbMails can assist with target mailbox creation. Verify licensing and the destination mailbox list before the production migration.

   • Step 5: Start IceWarp to office 365 migration

     • After mapping the mailboxes, click the ‘Start Migration’ button to initiate the migration process

       

     • You can now track the migration progress using the progress bar. When the migration is complete, EdbMails will display a confirmation message
     • Click the ‘View Log’ button to open the migration report, which provides a detailed summary of the entire process, including the total number of items migrated from each folder.

       

7. Icewarp to Office 365 post migration tasks

   • Step 1: Update the MX records to point to Office 365

     Update the MX records to route incoming emails to your target Office 365 server. Also, set up the Autodiscover record to allow Outlook to connect to the migrated mailboxes easily.

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

     Configure the Outlook profile for each user in your domain if Outlook has problems connecting to Office 365 mailboxes.

8. IceWarp to Office 365 migration troubleshooting

    For troubleshooting, visit Knowledge Base.

    For more queries, check , Frequently Asked Questions or contact support.

---

Additional resources:

• IMAP to Office 365 migration
• EdbMails IMAP migration software
• IMAP migration filters and incremental settings
• IMAP to Office 365 screenshots
• IMAP migration FAQ