Verify-only dry run mode
Perform a test migration to ensure everything is properly configured before commencing the Office 365 migration process without copying mailbox data. This mode helps detect issues and reduces migration risk.
Product Details
Check product scope and operation in this summary table.
| Item | Details |
|---|---|
| Protocol | Microsoft Graph API (OAuth 2.0) |
| Compatibility | Windows 11,Windows 10,and Windows Server (where supported .NET Framework and WebView2 Runtime run) |
| Authentication | Microsoft Edge WebView2 Runtime |
| Data path | Source mailbox → your PC → target mailbox (no Softaken mailbox relay) |
| Data types for migration | Emails,shared mailboxes,contacts,and calendars |
Designed for:IT admins and MSPs who regularly migrate mailboxes between accounts.
Comparison between Softaken Office 365 to Office 365 Migrator vs other methods
Features compared across desktop,PowerShell,manual,and Microsoft native approaches.
| Features | Softaken (desktop) | PowerShell / Scripts | Manual Method | Microsoft Native Tools |
|---|---|---|---|---|
| Primary fit | Best for IT admins and MSPs handling repeated mailbox migrations | Best for advanced scripting environments | For basic email migration only | Enterprise Microsoft-managed migration scenarios |
| Verify – only dry run | Built-in verify mode only (no target writes) | Need manual testing | Not available | Depends on the migration method |
| Delta and Resume | Built with SQLite state | Custom token handling | Limited | Depends on the programme |
| HTTP 429 handling | Safe / balanced / fast presets | Need manual retry | Weak throttling control | Admins manage throttling policies |
| Per-run audit pack | HTML/TXT reports generated automatically | Custom logging needed | Basic logs only | Limited reporting based on tools |
| Data path | Source mailbox → local PC → target mailbox (no Softaken mailbox relay) | Depends on script setup | Server-to-server email sync | Microsoft cloud-managed paths |
Validate against Microsoft documentation for your mailbox account pair before scheduling cutover.
Major Features and Advantages
Advanced capabilities for secure Office 365 account-to-account mailbox migration on Windows.
Direct mailbox-to-mailbox transfer
Migrate data directly between source and target accounts without third-party cloud servers. Sensitive emails,attachments,and documents remain within your migration environment.
Encrypted storage management
Keep mailbox data protected throughout migration. Encryption prevents unauthorized access while files are stored locally on your PC.
Advanced mailbox filters
Transfer mailbox data selectively. Filter emails,attachments,and mailbox items as required to improve storage usage,migration speed,and performance.
Microsoft Graph API integration
Safely connect Microsoft 365 accounts and move data using modern authentication—a secure bridge between Microsoft 365 and the migration application.
Persistent migration recovery
Continue migration from the last completed point after interruption. The software saves the session so you can resume without repeating the whole process.
Baseline and incremental delta pass
Transfer data with better speed and synchronization. Only updated mailbox items migrate after the initial sync,avoiding duplication of already migrated items.
Adaptive throttling presets
During migration,HTTP 429 errors and API blocks can slow progress. Speed and request limits adjust automatically with safe,balanced,and fast presets—useful for large tenant-to-tenant moves.
Operational Overview and Troubleshooting
Migration scenarios with benefits and common troubleshooting guidance.
| Migration scenario | Benefits | Troubleshooting common issues |
|---|---|---|
| User mailbox copy | Creates a mailbox copy to restore and recover the data | Authentication errors,Microsoft throttling errors,and missing mailbox items |
| Archive mailbox migration | Reduce the size of the main mailbox and improve performance | Slow archive migration,permission issues,and synchronization delays |
| Shared mailbox migration | Centralized team communication and preserve shared access | Permission loss and slow shared mailbox synchronization |
| Delta synchronization | Speed up migration and reduce bandwidth usage | Failed to detect new emails and missing folder updates |
| Pre-migration testing | Detect migration issues and prevent data loss | Authentication issues and missing mailbox items |
| Compliance reporting | Offer complete migration records and improve migration transparency | Incomplete audit reports and permission tracking problems |
For PST-based import,use the PST to Office 365 Importer. Contact supportwhen attaching failed_items.csv,and migration reports.
Office 365 Account-to-Account Migration in 5 Easy Steps
OAuth sign-in,filters,verify-only run,then baseline and delta before cutover.
OAuth to source
Open the software and sign in to the source Office 365 account with Microsoft OAuth (WebView2).
Select target
Open Upload to Office 365 serverand sign in to the target Office 365 account with OAuth.
Use filters
In advanced settings,choose a date range and exclude system folders,if required.
Verify only
Run verify only,check folder counts,and ensure no writes occur on the target.
Baseline and delta
Run initial migration,then delta before cutover. The report is generated automatically.
System Requirements
Basic system needs necessary to run Softaken Office 365 Account to Office 365 Account Migration.
OS
Windows 10 and newer versions (64-bit recommended)
Runtime
.NET Framework 4.7.2+ (net472 target)
WebView2
Microsoft Edge WebView2 Runtime for OAuth
Network
HTTPS to login.microsoftonline.com and graph.microsoft.com
Operational boundaries
- Ensure Microsoft 365 admin permissions and OAuth login settings are properly enabled.
- Use safe or balanced presets to avoid HTTP 429 error.
- Some special data types may not migrate.
- One source mailbox to one target per job. No support for bulk migration.
| Requirement | Details |
|---|---|
| RAM | Recommended 8 GB or more for large mailboxes |
| Disk | SQLite migration.db,space for logs,WebView2 profiles and Migration Reports output |
| Permissions | Graph delegated scope;admin permission:shared mailboxes need Full Access |
| Microsoft 365 | Valid Exchange Online mailboxes and proper licenses per Microsoft rules |
Recent Blogs
Try the demo build
Download demoIf the filename differs on your CDN,update this href once in the site template.
FAQs
Common questions about Microsoft 365 tenant-to-tenant and account-to-account mailbox migration.
The Office 365 tenant-to-tenant migration tool can migrate:
- Emails
- Calendars
- Contacts
- Tasks
- Notes
- Attachments
- Shared mailboxes
- Archive mailboxes
- Folder structure
Yes. This Exchange Online migration tool is completely secure and uses Microsoft Graph API and OAuth 2.0 authentication for safe mailbox transfer.
Yes. The program offers session recovery and auto-resume migration so you can continue after interruptions.
- Perform testing
- Backup your mailbox items
- Verify mailbox permissions
- Monitor migration logs
- Migrate during non-business hours
- Use modern authentication
HTTP 429 error reduces migration speed. Use safe and balanced presets,check Microsoft Graph API usage,and use incremental synchronization when possible.
What our clients say
Client reviews about Microsoft 365 tenant migration tool.
“Honestly wasn't expecting much going in,but this tool surprised me. We had a bunch of mailboxes with really heavy attachments that had caused problems with other solutions before. This one just... handled it. No sync errors,finished faster than I thought it would. Solid experience overall.”
“What stood out for me was how stable it stayed throughout the whole migration — no random crashes or slowdowns. The delta sync feature is genuinely useful,not just a checkbox on a feature list. Shared mailboxes came across with their folder structure intact,which saved us a lot of cleanup work afterward. If someone asks me to recommend an Office 365 to Office 365 migration tool,this is the one.”
“The incremental sync is what made the difference for us. We were running a phased migration,so new emails kept coming in during the process. This tool picked them up automatically on the next run — no duplicates,no manual intervention. Saved us hours of work we'd have otherwise spent double-checking everything.”
