Sometimes you have to check when the last backup of an Exchange mailbox database was taken. This is pretty simple, because the timestamps of the last full, incremental and differential backup is stored for each mailbox database. You can check these attributes using the Exchange Control Panel (ECP), or you can use the Get-MailboxDatabase cmdlet.
Backup successful, but no timestamp?
Take a look at this output. As you can see, there’s no timestamp for the last full, incremental and differential backup. But this database was successfully backuped some minutes before.
[PS] C:\Windows\system32>get-mailboxdatabase | select name, *backup*
Name : DB01
RetainDeletedItemsUntilBackup : False
Missing -status switch