Migrations.md

Migrations

This is a help page for the different types of migrations that can be done.

Table of Contents

1. Bittitan
   1. General info
   2. Disable throttling in EXO
   3. Timeout issues causing migration to fail
   4. Turn off Calendar assistant
2. Links to guides

Bittitan

Everything useful I've found for Bittitan migrations.

General info

Mailbox data is migrated from newest to oldest items. So the user gets their newest emails first.

Disable throttling in EXO

Disabled via support request in the admin center.

1. Log into the admin center as a GA for the customer.
2. Write "Increase EWS Throttling Policy" in the support search field.
3. Run tests and set the days to 90 and press "Update settings".

Timeout issues causing migration to fail

Add the following to the advanced options of the project.

ExtendedEwsTimeout=1
InitializationTimeout=8

Read more about the support options here

Turn off Calendar assistant

Note: This will disable the calendar assistant for all users in the tenant. This will need to be turned back on after the migration is complete. This is done to ensure that the calendar assistant doesn't interfere with the migration and break meetings and recurring meetings.

Get-EXOMailbox -ResultSize unlimited | Set-Mailbox -CalendarRepairDisabled $true

Note: Turn back on Calendar assistant for all users.

Get-EXOMailbox -ResultSize unlimited | Set-Mailbox -CalendarRepairDisabled $false

Links to guides

IP lockdown of migrations
Mailboxes over 100 GB/Large mailboxes
M365 to M365
On-Prem and Hosted Exchange to M365
Scoped inpersonation
OneDrive to OneDrive
All Bititan support options
MigrationWiz - Advanced Options & General Options