Blog Post

Exchange Team Blog
12 MIN READ

Troubleshooting Cross-Tenant Mailbox Migrations

The_Exchange_Team's avatar
The_Exchange_Team
Icon for Microsoft rankMicrosoft
Jun 28, 2024
In Part 1 of this series, we talked about cross-tenant (sometimes referred to tenant to tenant or T2T) mailbox migrations. In Part 2, we’ll cover how to troubleshoot issues you may encounter during c...
Updated Jul 16, 2024
Version 2.0
Documentation
exchange online
migration
troubleshooting
LM3327's avatar
LM3327
Copper Contributor
Jan 29, 2025

Hello Mirela_Buru hope all is well. Working on a T2T scenario where the secret expired in the target tenant. Haven't found much documentation on how to fix this issue. Any ideas would be greatly appreciated. -Lou Mandich

Mirela_Buru's avatar
Mirela_Buru
Icon for Microsoft rankMicrosoft
Jan 29, 2025

Hi Lou, nice to hear from you! I am good, hope you are doing well also. You can generate new client secret and update the migration endpoint with the new credentials.

So generate new Client Secret, step 17 Cross-tenant mailbox migration - Microsoft 365 Enterprise | Microsoft Learn

Store the value of client secret somewhere safe.
$AppId = "[Guid copied from the migrations app]"
$NewSecret = "your NEW password for the app"
# You can aslo get it from a file where you stored it
# $NewSecret = Get-Content "<path to file with the secret's value" -Raw
$Credential = New-Object -TypeName System.Management.Automation.PSCredential -ArgumentList $AppId, (ConvertTo-SecureString -String $NewSecret -AsPlainText -Force)
Then Set-MigrationEndpoint <name> -Credentials $Credential

https://learn.microsoft.com/en-us/powershell/module/exchange/set-migrationendpoint?view=exchange-ps#-credentials