Exchange 2010 has a security measure when it comes across a ‘poisoned’ mailbox’ in its Information Store database. If it deems the mailbox ‘dirty’ or ‘poisoned’, it will quarantine the mailbox. This keeps it safe from corruption and crashing.
Usually, quarantined mailboxes will be released after some hours (2-6hrs). In some cases, that may not be feasible, as user will have to stay without access to email.
You can follow these steps to resolve if critical: (you must be admin to do these)
1.Run Get-MailboxStatistics -identity ‘username’ | fl
2.Copy the mailbox GUID and keep it handy.
3.Open up the registry and navigate to HKLMSYSTEMCURRENTCONTROLSETSERVICESMSEXCHANGEIS<SERVERNAME>PRIVATE-(DB GUID)QUARANTINEDMAILBOXES(MAILBOX GUID)
4.Delete the key.
5.Restart the Information Store
6.Run an IISRESET
2.Copy the mailbox GUID and keep it handy.
3.Open up the registry and navigate to HKLMSYSTEMCURRENTCONTROLSETSERVICESMSEXCHANGEIS<SERVERNAME>PRIVATE-(DB GUID)QUARANTINEDMAILBOXES(MAILBOX GUID)
4.Delete the key.
5.Restart the Information Store
6.Run an IISRESET
Important repair considerations:
Consider repairing the mailbox upon expiration of 6hrs(release of mailbox from quarantine)
A. This example detects and repairs the folder view for the mailboxob@domain.com
New-MailboxRepairRequest -Mailbox obtest@domain.com -CorruptionType FolderView
B.This example detects and repairs all corruption types for mailboxes that have CustomAttribute2 set to RepairCorruption.
Get-Mailbox -Filter {CustomAttribute2 -like “RepairCorruption”} | New-MailboxRepairRequest -CorruptionType SearchFolder,AggregateCounts,ProvisionedFolder,FolderView
During the repair operation, there will be no mailbox access for the user.
The output of New-MailboxRepairRequest will be a number of Event IDs with a source of “MSExchangeIS Mailbox Store” and you will need to watch for the following events related to a repair request “0044,10045,01146,10047,10048,10049,10050,10051,10059,10062”
Ex-Shell 