CodeTwo Base.title

One at a time migration mode


You need to migrate all items one by one to help diagnosing migration problems or pinpoint corrupted items.


Run the migration in one at a time mode by introducing the following changes (valid for version 1.8 or newer):

  1. In the main window of the software, go to helplog files, this will open Windows Explorer window in the log files folder. Keep it open in background and go back to the software.
  2. Go to Advanced settings and change concurrency setting (Set the number of mailboxes that can be migrated at the same time) to 1.
  3. Close the application.
  4. Return to the log files folder you have opened in the background. Compress all log files folders to a .zip file and store somewhere safe in the case they are needed for comparison purposes. After that, delete old logs so the software can generate new, clean log files (this will be useful if you are doing this to diagnose migration problems).
  5. Go to the main installation folder, by default this is:
    C:\Program Files (x86)\CodeTwo\<name of the software>
  6. Open C2ExchangeMigration.Engine.dll.config file
  7. Find the following section:
    <setting name="MaxBatchItemsCount" serializeAs="String">
    Change the value from 150 to only 1, then save the changes and close the file.
  8. Open C2ExchangeMigration.Common.dll.config file
  9. Find the following section:
    • For CodeTwo Office365 Migration:
      <setting name="ConcurrencyMaxTargetConnectionsOffice365" serializeAs="String">
    • For CodeTwo Exchange Migration:
      <setting name="ConcurrencyMaxTargetConnectionsExchange" serializeAs="String">
    Change the value from 20 and 15 to only 1, then save the changes and close the file.
  10. Run the program and start the migration using Rescan button.
  11. Be aware migration may be considerably slower than previously.
  12. In the case you still experience migration problems please send to CodeTwo Support team all log files folders zipped. It might be necessary to also attach Application and System branches of you Event Viewer log files.

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