Symptoms
When a user logs on to a Microsoft Exchange 2010 mailbox by using a POP3 or IMAP4 client, the LastLogonTime, LastLogoffTime, and LastLoggedOnUserAccount property of the mailbox are not updated. Therefore, the Get-MailboxStatistics command returns an incorrect value when you run the command to query these properties.
Cause
This issue occurs because the Exchange store cannot recognize client strings from POP3 and IMAP4 clients.
Resolution
To resolve this issue, install the following cumulative update:
2661854 Description of Update Rollup 2 for Exchange Server 2010 Service Pack 2
More Information
For more information about MailboxStatistics properties, visit the following Microsoft website:
General information about MailboxStatistics propertiesFor more information about the Exchange 2010 store, visit the following Microsoft website: