Common Errors in ShareGate Migrations and How to Fix Them
Migrating to Microsoft 365 and SharePoint Online has become a strategic priority for many organisations.
Tools like ShareGate have simplified this process tremendously, offering a user-friendly and powerful interface.
However, like any migration tool, ShareGate is not immune to challenges. Even with the best tools, errors can arise during migrations.
That’s where expert partners like Adepteq, a trusted Microsoft solutions provider, come in. They help businesses navigate common ShareGate issues and ensure a smoother migration experience.
What is ShareGate?
ShareGate is a third-party migration tool designed to facilitate the move from legacy systems like SharePoint Server or file shares to SharePoint Online or Microsoft 365.
It offers bulk migration, reporting, permission management, and pre-check features that reduce the complexity and time spent during the migration process.
Despite its efficiency, ShareGate migrations can sometimes result in errors. These errors can stem from data complexity, configuration issues, or external dependencies.
Why Migrations Fail: The Core Causes
Data complexity and volume
Large volumes of data, especially unstructured content and nested folder structures, can overload ShareGate’s transfer process.
Metadata inconsistencies
Missing or broken metadata causes errors when transferring documents or lists.
Permissions problems
Migrating custom permissions or broken inheritance can create access issues post-migration.
Network interruptions
A slow or unstable network can break connections mid-transfer, resulting in incomplete or failed migrations.
SharePoint Online limitations
There are limitations in SharePoint Online like file name restrictions, URL path limits, and throttling — which ShareGate alone can’t override.
Common ShareGate Migration Errors and How to Resolve Them
Error 1: ‘Some files were not migrated due to path length limitations’
SharePoint Online has a maximum URL length of 400 characters. If the source file path exceeds this, ShareGate cannot move the item.
How to fix it
- Flatten the folder hierarchy before migrating.
- Use ShareGate’s pre-check to flag path issues.
- Rename folders or shorten file names in the source system.
Error 2: ‘The user mapping file contains invalid accounts’
This happens when ShareGate tries to map users that don’t exist in the destination tenant.
How to fix it
- Export your user mapping list and verify all accounts.
- Replace invalid or outdated accounts with correct ones.
- Ensure destination users are licensed in Microsoft 365.
Error 3: ‘Object reference not set to an instance of an object’
This generic .NET error can appear when ShareGate encounters an unexpected null value, typically with metadata.
How to fix it
- Clean up content types and metadata in the source library.
- Use ShareGate’s pre-check report to identify missing metadata.
- Ensure all required fields in the destination list are populated.
Error 4: Throttling by SharePoint Online
Microsoft enforces throttling to maintain performance. ShareGate may receive HTTP 429 or 503 errors during high data volumes.
How to fix it
- Schedule migrations during off-peak hours.
- Enable ShareGate’s built-in retry mechanism.
- Limit simultaneous operations in ShareGate’s settings.
Error 5: Workflow or version history issues
Some older workflows or version history items may not migrate correctly, causing partial transfers.
How to fix it
- Rebuild complex workflows manually in Power Automate after the migration.
- Limit version history or consolidate versions before the move.
- Check ShareGate’s compatibility with older SharePoint Designer workflows.
Best Practices for a Successful ShareGate Migration
Pre-migration assessments
Use ShareGate’s inventory and reporting tools to assess your current SharePoint environment. This helps identify problem areas before initiating the move.
Clean up your content
Remove obsolete files, folders, or unused libraries. Cleaning your data reduces migration time and the risk of errors.
Leverage user mapping and permission reports
Use ShareGate’s user mapping to align legacy user accounts with current Microsoft 365 identities. This avoids broken permissions and missing owners post-migration.
Use incremental migration
Instead of transferring all data in one go, break the migration into smaller phases. This helps isolate and resolve issues faster.
Engage a professional consultancy
Partnering with a Microsoft expert like Adepteq ensures you follow best practices and resolve complex ShareGate issues quickly and efficiently.
They provide planning, testing, remediation, and support throughout the migration journey.
How Adepteq Supports ShareGate Migrations
Strategic planning
Adepteq performs in-depth environment assessments and migration planning. They use ShareGate to execute low-risk and structured migrations.
Custom configuration
They customise ShareGate settings for your specific needs, including throttling controls, metadata mapping, and permission strategies.
Error remediation
If your migration runs into issues, Adepteq’s consultants step in to resolve them promptly — reducing business disruption.
Ongoing support
Even after your migration is complete, Adepteq provides continuous support to ensure long-term SharePoint success.
Case Study: Adepteq Streamlines a Government Migration Using ShareGate
A mid-sized UK government organisation wanted to migrate from SharePoint 2013 to Microsoft 365.
Their environment contained over 3TB of data, thousands of users, and several legacy workflows.
They attempted a migration using ShareGate internally but faced path length errors, user mapping issues, and severe throttling.
Adepteq was brought in to assist. Their team:
- Used ShareGate’s pre-checks to identify risky items
- Created a folder restructuring plan
- Consolidated metadata fields
- Mapped users and cleaned permissions
- Staggered the migration to avoid throttling
The result was a 100% successful migration with zero data loss, full version history retention, and optimised permissions — all completed ahead of schedule.
Future-Proofing Your SharePoint Environment Post-Migration
Once you’ve successfully migrated using ShareGate, it’s essential to maintain and optimise your new SharePoint Online environment.
Set governance policies
Define content retention rules, permissions strategies, and content classification.
Train your users
Provide SharePoint Online training to ensure users can find and use their content effectively.
Monitor with ShareGate
Even after migration, ShareGate offers powerful reporting and security tools to maintain compliance and performance.
Conclusion
ShareGate remains one of the most trusted tools for migrating to SharePoint Online.
While errors during migration are common, they are entirely manageable with proper planning, configuration, and support.
Organisations that partner with experts like Adepteq not only experience smoother transitions but also gain lasting value from their SharePoint investment.
Understanding common errors — from metadata issues to throttling — and how to fix them empowers you to take control of your migration.
With a proactive strategy and the right tools, your journey to the cloud can be secure, seamless, and successful.
