Solve Google Workspace Migration Failure With Expert Insights

Google Workspace Migration Failure Resolved Via Smart Fixes

Published By Siddharth Sharma
Anuraag Singh
Approved By Anuraag Singh
Published On January 17th, 2024
Reading Time 9 Minutes Reading
Category G Suite, Migration

As Google continues to improve its business productivity apps, many young entrepreneurs look to move their data and try out the cloud-based platform for themselves. However, while shifting, they might face a Google Workspace migration failure without warning.

These problems are accompanied by some error codes that confuse newly appointed admins. Moreover, the main cause of these errors is the inherent limitations of the default migration tool that Google itself provides.

Therefore, we compile all the different problems that users may witness and give a sure-shot remedy as well so let’s start with the error codes first.

Understand Google Workspace Migration Failure With Error Codes

Error Code Error Name Causes


400 Bad Request This indicates the issues that exist in the source account itself. These can be further broken down into cases where

  • You are attempting to push in data types that are not permitted by Google or your Organization.
  • Google has identified malicious macros and marked one or more emails/data as potential virus delivery agents.
  • If emails are in a format that violates the standard Request For Comment 822 syntax
  • Email + attachment size exceeds the 25 MB threshold of Gmail.
Sometimes the error may be a false positive. If this is the case then just send the migration request again.

After a second pass, the error remerges:

  • Redo the source data cleanup
  • Check and remove invalid files
  • Eliminate virus-ridden emails
  • Bring emails back to RFC822
  • Then, move emails & attachments separately

If for some reason you still need to add the invalid file type into the new G Suite environment then use this workaround:

  • Upload the invalid file types into Google Drive
  • Then share the Drive link in place of the actual file
401 Unauthorized A permission-level error arises if Google Workspace Migration cannot verify the credentials. One of the following might be your particular scenario:

  • Incorrect username or password.
  • Incompatible with the OAuth policy or Typing the wrong 2FA code.
  • Server-side authentication issue.
  • Workstation IP range blocked due to security concerns.
  • Permission valid for a set of users not all
To fix this Google Workspace Migration issue consider the following.

  • Verify the admin impersonation rights once more.
  • Re-enter authentication credentials.
  • Regenerate 2FA code and type it correctly
  • Conduct migration in officially designated IP addresses.
  • Retry the login after some time.
  • Check user authentication log and trigger missing permissions
403 Forbidden Triggers when Gmail or Drive services cannot be accessed via Google Admin Console.

  • Daily API limit already crossed.
  • Limit breaching may also be due to user requests, projects, and file sharing
  • Global Admin policy blocks access to the requested action.
Possible fixes are:

  • Allow access to Gmail or Drive services
  • Then, put in an alert system to notify daily API calls.
  • Instruct users to remove all permission restrictions beforehand.
  • Ensure that no admin policies interfere with the migration project.
409 Conflict A conflict arises when two different source data points are fighting for the same target storage space.

  • Moreover, its impact is further amplified as the traditional method is not able to resolve it. The majority of the time it’s due to the following user-level issue.
  • Invalid label creation. The folders(labels) do not follow the accepted naming convention.
  • Labels that are to be moved were deleted during or before migration.
  • Multiple copies of the same Label are being shifted
  • Rigorous clean-up operation during inventory accumulation is one way to prevent such an issue.
  • Another task that admins can do is forbid label creation/ deletion while the migration is underway.
  • Sometimes changing the label name is enough to resolve the issue
410 Gone Transient errors or temporary errors happen all of a sudden during a migration.

If your error code resembles 5XX then use the following identifications:
500 Backend error

  • 502 Bad Gateway
  • 503 Service Unavailable
  • 504 Gateway Timeout
Best advice is to wait and watch. Otherwise, initiate a new delta migration and seek assistance from the Google Workspace Support team.
429 Too Many Requests Occur when the migration tool is overwhelmed with numerous requests.

  • Miscommunication between migration teams is one of the most overlooked issues. It results in multiple repetitive messages all at once.
  • If these are from different IPs(workstations) Google might interpret it as an attack and shut down the server entirely.
  • Keep all teams in charge of the migration on the same page.
  • Create provisions for real-time communication.
  • Use an exponential backoff strategy to allow the server a recovery period.
  • Make sure each subsequent migration request has ample time interval between them
  • Reschedule migration if necessary

Other Minor Google Workspace Data Migration Errors & Their Resolutions

Google Workspace data migration error 18017

Cause: It occurs when.

  • GMS is unable to verify the provided IMAP credentials.
  • The user is inactive or suspended in the source domain.

Fix: Attempt the following.

  • Recheck the credentials you are using.
  • Unsuspend users whose data is to be migrated.

Google Workspace data migration error 18015

Cause: Gmail account not setup properly

Fix: Allow “Less secure apps to connect with GMS (Google migration service)”

Sometimes users may get Google Workspace migration failed during estimation itself. Here there is no specific error code that helps identify the core issue. So users must perform a hit and trial to get to the underlying cause.

These are just the tip of the iceberg when it comes to migration error codes. To minimize their frequency IT admins must have a concrete plan in place. As a result, they need some standard guidelines. Don’t worry as we have all the relevant information right here in the next section.

Best Practices to Overcome Google Workspace Migration Limitations

  • Make sure no other program has access to the source when the migration is in progress.
  • Validate and sign all TLS certifications before starting with the migration.
  • Complete OAuth verification for the app on your local machine.
  • Disable antivirus and other hurdles that may stop the app.
  • Use a professional alternative instead of manual migration.

Eliminate Google Workspace Migration Failure by Using A Professional Alternative

The only solution that you would ever need is the state-of-the-art Office to G Suite Migration tool. With a simplified UI, this utility is designed to make even the most complex migrations easy and efficient. So try out the tool and witness the difference for yourself.

Download Now Purchase Now

Easy steps to use the tool are

Step 1. Download the utility on your machine, Launch it, and pick G Suite as both Source and destination.

Start screen

Step 2. Then, make the Workload Selection mark boxes along Email, Document, Contacts, Calendars and Apply the necessary Date Filter.


Step 3. Then, type in the Admin Credentials  Perform source and target Validation.

enter domains

Step 4. Create a User Mapping with the help of any one of the methods present (Fetch Users, Import Users, Download Template).

start the migration

Step 5. Finally, Preview the users inside the dashboard, Validate all Selected Users, and Start Migration.


Real Scenarios that Indicate the Superiority of Automated Software

Here we highlight how the advanced feature set of the utility gives real-life benefits to users across industries.

Slow Data Transfer Speed

User Query: “I was recently hired as the technical head of the local hospital. With this new role came an additional responsibility to lead a complex data transfer project. Additionally, the native method to shift the data was too slow, and we cannot risk the patient’s well-being for such a long time. Which led us to look for better alternatives that can skip over the Google Workspace migration failure present in the market.”

Solution:  “During my previous experience, we utilized a well-renowned product for a similar data transfer. As a result, we got it, and like previously, the tool did not disappoint. It quickly transferred all the data to the desired location in record time.”

Data Mapping Challenges

User Query: ”I, as an admin of a financial institution, was given the task to shift our data to Google Workspace. At first, my plan was to involve the default migration solution that Google provides for free. As I didn’t know how to import contacts to Google Workspace, this would be an easy way. Moreover, I thought this would end up saving migration costs, but I made a hasty prediction. This is because the tool took up a lot of unnecessary time due to the many mapping errors.”

Solution: “After asking experts for their opinions on a better solution, all of them recommended a professional tool. The reason is that the tool has multiple custom mapping options. Therefore, once we brought the tool, the result was a successful migration with no data loss.”


In this blog post, we covered everything related to Google Workspace migration failure that a user needs to know. Not only did we cover the most common error codes that users may face we also gave some best practices to avoid the issues. Moreover to get a complete error-free data transfer users can go for the professional utility.

Top 5 Frequently Asked Questions About Google Workspace Migration Failure

Q1. “Why are some of my emails missing after migrating?”

Common Causes: This issue can result from data mapping errors, data corruption during migration, or issues with email filters not properly transferring. It may also occur if the user goes for the manual migrator, which often fails to capture all email folders. No wonder people ask “is Office 365 better than Google Apps?“. Additionally, to overcome this issue, the user can very well go for the advanced utility explained above.

Q2. “I can’t access my files in Google Drive after migration. What should I do?”

Common Causes: Access issues often stem from authentication discrepancies or incorrect sharing settings on Google Drive files. Moreover, the migration process might not correctly transfer permissions. Here, the admin may have to re-assign permissions manually.

Q3. “Why are my calendar events showing up at the wrong times after switching?”

Common Causes: Time zone differences between the source and destination platforms, as well as data format inconsistencies, can lead to calendar events displaying inaccurately. Another reason for this Google Workspace Migration Failure is when the original message is not compliant with the RFC 5322 standard.

Q4. “My contacts list looks incomplete after migrating. How can I recover missing contacts?”

Common Causes: Moreover, missing contacts may result from data mapping errors, data corruption, or issues with the migration tool not correctly transferring contact details.

Q5. “I’m experiencing slow performance on my new platform. What could be causing this?”

Common Causes: Slow performance can be due to data volume exceeding the new platform’s capabilities, inadequate bandwidth, or issues with third-party applications integrated into the new platform.