In Microsoft 365 / Exchange Online, to connect a soft deleted mailbox, you have need to use the cmdlet New-MailboxRestoreRequest to restore the mailbox to another user.

Get-Mailbox -SoftDeletedMailbox | select guid

Get-Mailbox <NewMailbox> | select guid

New-MailboxRestoreRequest -SourceMailbox <GUID> -TargetMailbox <GUID of new mailbox> -AllowLegacyDNMismatch

To check the status of the restore:

Get-MailboxRestoreRequest | Get-MailboxRestoreStatistics

References:

Reddit

If you are noticing seemingly random RDS session freezing on Windows 10/11 clients, this registry key might help. It disables the UDP protocol for RDP connections, which Microsoft enabled by default since Windows 10 1809/1909. I have had this issue occur on Windows 10 21H2.

HKLM\Software\Policies\Microsoft\Windows NT\Terminal Services\Client

DWORD fClientDisableUDP 1

A reboot of the machine was not needed, after closing the RDP session and reconnecting, TCP was being used. You can check which protocol is being used by clicking the symbol at the top:

References:

https://www.michaelmaw.com/how-to-fix-remote-desktop-freezing/

https://community.spiceworks.com/topic/2269433-remote-desktop-randomly-freezes-up