Troubleshoot the data migration service

If you encounter problems when migrating from a Microsoft Exchange Web Services (EWS) environment, verify:

Step 1: Servers can reach and recognize EWS

Select the Synchronization, Notification, Availability, and Automatic Replies option on the Exchange Server tab in the Microsoft Remote Connectivity Analyzer tool to verify that servers can reach and, through the Autodiscover service, recognize EWS.

Step 2: The logs show the data migration service can communicate with Exchange

Check the Exchange server Internet Information Services (IIS) logs for the SyncFolderItems call with response code 200.

Step 3: AD Conditional Access policies

Check whether you’re using Conditional Access policies on your Microsoft Active Directory. If so, turn off the policies and try migrating again. For more information, consult your Microsoft documentation.

Step 4: Exchange impersonation

For more information, consult your Microsoft documentation on how to set up Exchange impersonation.

Step 5: TLS certificates

Verify your TLS certificates are signed and valid. For details, go to Set up your TLS certificate.

Step 6: Exchange user account

Verify the Exchange user account is a valid account and the mailbox is turned on. Also, check that the Exchange mailbox isn't corrupt.

Step 7: Migration client ID

Verify that the following service account client ID appears in the list of clients that have access to mail and migration APIs:

955661971872-ie97v0ns6ndb19rbr9nlpkahpmfk9ugf.apps.googleusercontent.com

To check the client ID:

1. Sign in to your Google Admin console.

   Sign in using an account with super administrator privileges (does not end in @gmail.com).

2. In the Admin console, go to Menu  SecurityAccess and data controlAPI controlsManage Domain Wide Delegation.
   You must be signed in as a super administrator for this task.
3. The client ID should be listed under API clients.
4. If the client ID isn't listed, click Add new and enter the following ID:

   955661971872-ie97v0ns6ndb19rbr9nlpkahpmfk9ugf.apps.googleusercontent.com

5. For OAuth scopes, copy and paste the following comma-delimited list of scopes:

   https://mail.google.com/,
   https://googleapis.com/auth/email.migration,
   https://googleapis.com/auth/gmail.insert,
   https://googleapis.com/auth/gmail.labels

6. Click Authorize.
7. Point to the new client ID, click View details, and make sure that every scope is listed.

   If a scope is not listed, click Edit, enter the missing scope, and click Authorize. You can't edit the client ID.

Step 8: The relevant Google service

Check that you turned on the target Google service (Gmail, Contacts, or Calendar). For details, go to Turn a service on or off for Google Workspace users.

Step 9: The super administrator

Check that a super administrator is assigned to the Google Workspace domain.

Step 10: Server gets connections from Google mail servers

For details, go to Google IP address ranges for outbound mail servers.

Blocking issues when migrating from an IMAP server, Gmail, or a Google Workspace account might indicate an obstacle accessing the mailbox. Try to access the mailbox using an IMAP email client such as Mozilla Thunderbird, Apple Mail, or Microsoft Outlook. Doing so ensures the mailbox has IMAP access and that you have the correct username and password.

If you still have issues, confirm:

Step 1: Migration client ID

Verify the following service account client ID appears in the list of clients that have access to mail and migration APIs:

955661971872-ie97v0ns6ndb19rbr9nlpkahpmfk9ugf.apps.googleusercontent.com

To check the client ID:

1. Sign in to your Google Admin console.

   Sign in using an account with super administrator privileges (does not end in @gmail.com).

2. In the Admin console, go to Menu  SecurityAccess and data controlAPI controlsManage Domain Wide Delegation.
   You must be signed in as a super administrator for this task.
3. The client ID should be listed under API clients.
4. If the client ID is not listed, click Add new and enter 955661971872-ie97v0ns6ndb19rbr9nlpkahpmfk9ugf.apps.googleusercontent.com.
5. For OAuth scopes, copy and paste the following comma-delimited list of scopes:

   https://mail.google.com/,
   https://googleapis.com/auth/email.migration,
   https://googleapis.com/auth/gmail.insert,
   https://googleapis.com/auth/gmail.labels

6. Click Authorize.
7. Point to the new client ID, click View details, and make sure that every scope is listed.

   If a scope is not listed, click Edit, enter the missing scope, and click Authorize. You can't edit the client ID.

Step 2: The relevant Google service is turned on

Check that you turned on the target Google service (Gmail, Contacts, or Calendar). For details, go to Turn a service on or off for Google Workspace users.

Step 3: A super administrator is assigned

Check that a super administrator is assigned to the Google Workspace domain.

Step 4: Your server gets connections from Google mail servers

For details, go to Google IP address ranges for outbound mail servers.

Step 1: Verify message is missing

1. Follow the instructions in Why is the number of messages greater than the items migrated?
2. If there are still messages missing, continue to step 2.

Step 2: Check setup steps

Check that you completed the steps in Prepare your source account.

Step 3: Search for email header

Make sure a message isn't mislabeled:

1. Get the message-ID of a missing message from the source account. You can find the message-ID in the message header.

   For details, go to Trace an email with its full headers.

2. In the new account, use the rfc822msgid: Gmail search operator to search for the message-ID.

   For details on using a search operator, go to Search operators you can use with Gmail.

3. If the message can't be found in the new account, continue to step 4.

Step 4: Check error report

1. Locate the item error report.

   For details, go to Monitor a migration.

2. If the message shows as failed in the report, go to Data migration service error messages and follow the instructions for the corresponding error message.
3. If the message isn't in the report and you're migrating from Gmail or Google Workspace, make sure that the mailbox on the source account:
   • Doesn't have an IMAP folder size limit
   • Shows all labels in IMAP

   For details, go to Get email from another email platform.

If you have an email folder missing after a migration, contact your source email service provider for help with resolving the issue with the folder.

If the issue can’t be resolved, you could delete the folder and run the migration again. Any email messages contained within the folder are also deleted, however.

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