Permanently delete disconnected mailboxes in Exchange 2010

This could be usefull when moving users and you would like to free up some space.

# Permanently delete disconnected mailboxes.

List disconnected:
Get-MailboxStatistics -Server MAILSERVER | ?{$_.DisconnectDate -ne $null} |ft Displayname,Identity,Disconnectreason

Remove by using mailbox database and mailbox identity.
remove-storemailbox -Database MAILBOXDATABASE -Identity “8be4d91d-6380-4dcd-b5a4-d003f4ec3f14” -MailboxState Disabled

Lync server 2013 Error: Prerequisite installation failed: SqlInstanceRtc

When installing Lync server 2013  this error bugged me.

What could be wrong. with SqlExpress? Tried installing “sqlexpr_64.exe” from the DVD and here is my problem.

Something went wrong when I downloaded the ISO image. Deleted the downloaded imaged and did a new download. After mounting the image I ran setup.exe and the same error appeared. I then remembered that Lync setup copies setup files to the cache. Deleted Lync setup cache directory from “C:\ProgramData\Microsoft\Lync Server\Deployment”. After this the install ran perfectly.