Understand migration scan reports

Supported editions for this feature: Business Starter, Business Standard, and Business Plus; Enterprise Standard and Enterprise Plus; Education Fundamentals, Education Standard, and Education Plus; Essentials Starter, Essentials, Enterprise Essentials, and Enterprise Essentials Plus; Nonprofits; G Suite Basic and G Suite Business. Compare your edition

You can get detailed information on the data in your Microsoft Exchange Online migration scan.

You can review:

  • Email data
  • Calendar data
  • Contact data

User report fields & descriptions

Report field Description
Source user Email address of the Exchange Online user
Status Status of the user's migration scan:
  • Running—Migration scan is in progress.
  • Failed—Migration scan didn't complete because of discovery issues. To troubleshoot, check the migration report for the specified error.
  • Completed—Migration scan completed successfully. Any messages or labels that didn't scan are listed in the migration error report.
Note: This report does not have a Skipped status because users are never skipped.
Emails scanned Number of messages scanned successfully for the user (including messages that were skipped in an earlier migration scan)
Calendars scanned Number of calendars successfully scanned for the user (including additional calendars)
Calendar events scanned Number of events successfully scanned for the user
Contacts scanned Number of contacts successfully scanned for the user
Discovery failures Total number of:
  • Folders whose messages and associated subfolders were not discovered, either partially or fully
  • Calendars whose events were not discovered, either partially or fully
  • Contact folders with contacts and subfolders that were not discovered, either partially or fully
  • Root-level contacts that were not discovered (This failure is only counted once, even if it affects multiple contacts at the root level.)
Status details If the user's account is discovered, the status is OK. For accounts that are not discovered, you get the Failed to discover emails or calendars for the user. For details, check the migration report error message.

Migration report fields & descriptions

Report field Description
Status The migration scan status of the item:
  • Success—The item scanned.
  • Warning—The item scanned, but failed to complete as expected (for example, when an email scanned without the label associated with it).
  • Error—The item didn't scan due to an error. Learn more about how to resolve common error messages.
  • Skipped—The item was skipped.
Error/warning code & description The code and message associated with the error or warning status. Learn more about how to resolve common error messages.
Processing start time

Processing end time

 The migration scan start and end time
Source type & source identifier
  • Exchange Online Email Folder Crawler: mailboxes/user_email/folders/folder_id
  • Exchange Online Email Folder: mailboxes/user_email/folders/folder_id
  • Exchange Online Email Message Crawler: mailboxes/user_email/folders/folder_id
  • Exchange Online Email Message: mailboxes/user_email/messages/message_id
  • Exchange Online Calendar Crawler: users/{user}
  • Exchange Online Calendar: users/{user}/calendars/{calendar}
  • Exchange Online Event Crawler: users/{user}/calendars/{calendar}
  • Exchange Online Event: users/{user}/calendars/{calendar}/events/{event}
  • Exchange Online Contact Folder Crawler: users/{user}/contactFolders/folder_id
  • Exchange Online Contact Folder: users/{user}/contactFolders/folder_id
  • Exchange Online Contact Crawler: users/{user}/contactFolders/folder_id
  • Exchange Online Contact:
    users/{user}/contacts/contact_id
  • Exchange Online Contact Category: users/{user}/contact/{contact_id}/categories/category_id

Resolve common error messages

Error message Description & troubleshooting help
The connection is invalid. Please disconnect and reconnect then try again. The connection is invalid. Disconnect the connection and create a new connection. Then run the migration again.
Temporary error occurred A transient error. Re-scan the data.
User not found A user wasn't found. Try the following steps:
  • Confirm the email addresses in the CSV file you uploaded in Select users to scan are correct. Then, update any incorrect email addresses in the file and try uploading it again.
  • Export the user report and make sure the Exchange Online users are correct.
  • In the migration settings, make sure you chose to copy user addresses that aren't found in the list you uploaded.
The source email address is invalid The user is not present in Exchange Online. Add the user and re-scan the data.
Connection not in usable state Your connection contains errors and is no longer in a usable state.

Disconnect and create a new connection. For details, go to Connect to your Microsoft account.
All required OAuth scopes have not been granted access Some or all of the required OAuth scopes haven't been granted domain-wide delegation.

Disconnect and create a new connection. For details, go to Connect to your Microsoft account.
Invalid user provided in migration mapping A user email ID in the list of users to scan is invalid or is not a Google email ID.
  1. Remove the user list.
  2. Correct the user list.
  3. Upload the corrected list of users.
For details, go to Select users to scan.
Unable to fetch resources for crawling source mailbox

Failed to crawl the source mailbox

Failed to authenticate with the source mailbox

Deadline hit while crawling the source mailbox

Source mailbox quota has exceeded

 These are temporary issues. Wait a few hours then re-scan the data.
The source mailbox concurrency limit has been exceeded Users should avoid using their mailboxes while a migration is running. Re-scan the data to fix this issue.
Certain draft emails can fail due to missing 'From' header. Please check the headers of the draft emails and try running a delta migration. Draft email messages in Outlook must have exactly one email address in the From field or they will trigger this error.
  1. Ensure your draft email messages have one address in the From field.
  2. Re-scan the data.
Calendar quota has exceeded. Please try again later.

Unable to fetch resources for writing to target calendar. Please try running a delta migration.

Source user fetch failed for attendees: <username1>,<username2>

Source user fetch failed for organizer: <username1>

 This is a temporary issue. Wait for a few hours and then re-scan the data.
Access is denied. Check credentials and try again. If you receive this message during a data migration:
  1. Disconnect and reconnect your Exchange Online account.
  2. Re-scan the data.


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