Stellar Migrator for MS Exchange — Complete Guide & Features

How to Use Stellar Migrator for MS Exchange: Step-by-Step TutorialStellar Migrator for MS Exchange is a tool designed to simplify mailbox migration between Microsoft Exchange environments and to/from other platforms (such as Office 365). This step-by-step tutorial walks through planning, preparation, installation, migration execution, verification, and post-migration tasks. Follow each section carefully to reduce downtime, avoid data loss, and ensure a smooth transition.

Before you begin: planning and prerequisites

• Check system requirements: Ensure your source and target servers meet Stellar Migrator’s supported Exchange versions and system specs.
• Back up mailboxes: Create backups of source mailboxes and Exchange databases before migrating.
• Accounts and permissions: Prepare an account with administrative privileges on both source and destination Exchange environments (Organization Management role or equivalent). For Office 365/Exchange Online, assign Exchange Administrator or Global Administrator as required.
• Network and firewall: Ensure necessary ports (RPC, MAPI/HTTPS, EWS for Exchange Web Services, and others depending on your configuration) are open between the tool and both servers.
• Licensing: Obtain a valid Stellar Migrator license matching the number of mailboxes and features you need. The trial version typically limits migration volume.
• Inventory and scope: Make a list of mailboxes, distribution groups, public folders, calendars, PST files, and other items to migrate. Decide whether to migrate all data or a subset (date ranges, folders, or specific mailbox items).
• Communication plan: Notify users about migration windows, expected disruptions, and post-migration verification steps.

Step 1 — Install Stellar Migrator

1. Download the latest Stellar Migrator for MS Exchange installer from Stellar’s official site.
2. Run the installer on a machine that has network access to both source and destination Exchange servers. A dedicated migration workstation or server is recommended.
3. Follow the on-screen prompts: accept the license agreement, choose an installation folder, and complete installation.
4. Launch the application and activate it using your license key (or continue in trial mode for testing).

Step 2 — Configure connections

1. Open Stellar Migrator and choose the migration scenario (Exchange to Exchange, Exchange to Office 365, Office 365 to Exchange, or Exchange to PST/IMAP/other).
2. Add the source Exchange server details:
   • Server name or IP
   • Authentication method (Windows/NTLM, Basic, or OAuth where supported)
   • Admin credentials with necessary permissions
   • If using Office 365, provide tenant admin credentials and configure modern authentication if required
3. Add the destination server details similarly.
4. Test both connections using the tool’s “Test Connection” or equivalent feature to validate connectivity and permissions.

Step 3 — Discovery and mapping

1. Use the discovery feature to enumerate mailboxes and other items on the source server. This typically lists user mailboxes, shared mailboxes, archive mailboxes, public folders, and resource mailboxes.
2. Export or review the discovered inventory. Identify mailboxes to be migrated and any that should be excluded.
3. Map source mailboxes to destination mailboxes:
   • Use automatic mapping where Stellar Migrator matches users by SMTP address or UPN.
   • For cross-tenant or differently named accounts, map manually by selecting a target mailbox for each source mailbox.
4. Optionally, create new mailboxes on the destination if they don’t exist (many migration tools provide this ability; confirm Stellar’s current feature set and permissions required).

Step 4 — Select migration options and filters

1. Choose migration scope for each mailbox:
   • Full mailbox
   • Selected folders (Inbox, Sent Items, Calendar, Contacts)
   • Item-level filters (date range, message size, item types)
2. Decide whether to migrate:
   • Deleted items and Recoverable Items
   • Folder permissions and public folder permissions
   • Calendar free/busy information
3. Configure retry and throttling options to prevent overload of Exchange servers. Set concurrency limits and time windows for migration tasks.
4. Enable logging and choose a log location for troubleshooting.

Step 5 — Run a pilot migration

1. Select a small set of non-critical mailboxes (typically 5–10) representing different mailbox sizes and types (large mailbox, shared mailbox, archive enabled).
2. Run the migration using the configured options. Monitor job progress using the tool’s dashboard.
3. Verify migrated mailboxes on the destination:
   • Check folder structure, message counts, attachments, calendar entries, and permissions.
   • Test send/receive functionality and calendar free/busy visibility if applicable.
4. Gather user feedback and adjust mapping, filters, or throttling settings as needed.

Step 6 — Perform full migration

1. Schedule migration windows during off-peak hours to reduce impact on users.
2. Start the batch or staged migration, monitoring:
   • Job queues and progress percentages
   • Errors and warnings in logs
   • Server performance counters (CPU, memory, disk I/O) to avoid saturation
3. Handle errors:
   • Common errors include authentication failures, throttling, network timeouts, and item-level corruption.
   • Retry failed items or re-run migration for affected mailboxes after resolving root causes.
4. For large deployments, consider migrating in waves (by department or region) to control load and support.

Step 7 — Delta sync and cutover

1. After the initial full migration, run a delta (incremental) sync to capture items created or modified since the initial pass. This reduces data loss at cutover.
2. Re-run delta syncs until you’re ready to cut over. Verify that delta pass shows minimal or zero changes before final cutover.
3. Cutover steps:
   • Update DNS/Autodiscover records if moving to a new environment; lower TTL beforehand to speed propagation.
   • Reconfigure mail flow (MX records) if required.
   • Disable or convert old mailboxes per your retention policy.
   • Communicate final cutover time to users.

Step 8 — Post-migration verification and cleanup

1. Verify user access and mailbox integrity on the destination:
   • Check message counts, folder structures, calendar entries, and shared folder permissions.
   • Ensure mobile devices and mail clients can connect and sync properly.
2. Re-assign mailbox permissions and re-create any custom transports, rules, or connectors that were environment-specific.
3. Archive or decommission the source environment according to your retention and compliance policies. Keep backups for a required retention period.
4. Review logs and document the migration outcome, issues encountered, and resolutions for future reference.

Troubleshooting common issues

• Authentication failures: Confirm credentials, MFA/OAuth requirements, and that the account has required roles.
• Throttling/slow performance: Reduce concurrency, schedule during off-hours, or request temporary throttling limits from Microsoft for large migrations.
• Item-level corruption: Export problematic items to PST, repair if possible, and re-import to destination.
• Mail flow disruption: Verify MX and connector settings, and ensure Autodiscover is pointing correctly.

Best practices and tips

• Run pilot migrations to validate the process and user experience.
• Keep communication frequent and clear with end users about expected changes and any required client reconfiguration.
• Monitor server health throughout; migrations can stress Exchange servers.
• Use incremental/delta syncs to minimize data loss.
• Document mapping, settings, and exceptions for audit and rollback planning.

When to engage support or professional services

• Large or complex environments (thousands of mailboxes, hybrid setups) often benefit from vendor professional services.
• Persistent errors tied to on-prem Exchange configuration or network infrastructure may require Exchange admins or Microsoft support.
• If compliance, litigation holds, or archive migration is involved, consult legal/compliance teams before decommissioning.

Stellar Migrator for MS Exchange streamlines many migration tasks, but success depends on planning, testing, and careful execution. Follow the steps above, adapt settings to your environment, and keep verification and rollback plans ready.