How to recover data from a Deleted or Inactive mailbox in Exchange Online
The default mailbox retention in Microsoft 365 is 30 days, we can recover deleted/Inactive user’s mailbox to a new user or to a temporary user.
Please note that if you remove license form a user, mailbox will also be removed, once we reassign the license, mailbox will reconnect automatically.
To list all the deleted mailboxes
Get-Mailbox -SoftDeletedMailbox | select DisplayName, PrimarySmtpAddress, WhenSoftDeleted, RecipientTypeDetails, GUID, CustomAttribute6, DistinguishedName
#You can export this list in CSV.
Get-Mailbox -SoftDeletedMailbox | select DisplayName, PrimarySmtpAddress, WhenSoftDeleted, RecipientTypeDetails, GUID, CustomAttribute6, DistinguishedName | Export-Csv C:\Temp\Deletedmailboxes.csv -NoTypeInformation
#In the output file we can find the mailbox information we want to recover.
We can also find just one mailbox from deleted mailboxes.
Get-Mailbox -SoftDeletedMailbox -Filter {name -like "*Mailbox Name*"} | fl Guid, DistinguishedName
Note down the mailbox GUID from above command and run below commands to restore the mailbox.
#Get details of inactive mailbox
$InactiveMailbox = Get-Mailbox -SoftDeletedMailbox -Identity 532f8e25-b435-4a17-b253-9097632680a1
#Run restore command
New-MailboxRestoreRequest -Name UserName-Restore -SourceMailbox $InactiveMailbox.DistinguishedName -TargetMailbox <DN of TargetMailbox> -TargetRootFolder Restore -AllowLegacyDNMismatch
Now, you can trace the restore using below command
#To get all the restore request.
Get-MailboxRestoreRequest | Get-MailboxRestoreRequestStatistics
#To get just one restore request.
Get-MailboxRestoreRequestStatistics -Identity RestoreRequest