Exchange 2013 Quarantine Mailbox

Exchange 2013 Quarantine Mailbox

To find the quarantine mailbox -  Get-mailbox administrator | fl *isq*

The following registry path is created used to store the keys:

HKLM\SYSTEM\CurrentControlSet\Services\MSExchangeIS\\Private-{db guid}\QuarantinedMailboxes\{mailbox guid}

In this path the following keys will be created:

    CrashCount: the amount of crashes detected
    LastCrashTime: the timestamp of the last occurance of a crash
    QuarantineState: is a mailbox quarantined or not
    QuarantineTime: the time the mailbox is placed in quarantine

If the issue doesn’t occur again in two hours the registry key used to store the counter is deleted. The 2 hours is a value which can’t be changed. But there are two other interesting keys:

    MailboxQuarantineCrashThreshold: how many issue may occur before a mailbox is put in quarantine
    MailboxQuarantineDurationInSeconds: how long is the mailbox placed in quarantine

When mailbox put in quarantine it doesn't passes to OPEN_AS_ADMIN flag

Solution:

To manually release the mailbox you will first need to know the GUID of the mailbox. You can lookup the GUID by using the get-mailboxstatistics cmdlet just like this:

Get-Mailbox support |select name, GUID
Once you have found the GUID you will need to find the corresponding registry path. As discussed earlier each poisoned mailbox has the key MailboxQuarantineDurationInSeconds modify the value to for example 0 or 1. After you’ve made the registry key change perform one of the following tasks:

•     Dismount/mount the database
•     Restart the Information Store
•     Reboot your server