Check Size of Email Attachments
Using your email client, navigate to the email attachments that you would expect to have been reduced in size. Check that the file sizes are smaller.
You can use Outlook Web Access via your web browser (https://<computer>/owa) to view the optimised attachments. If you are using a different mail client you may need to force synchronization before you see any changes.
It is worth opening the attachments that have been reduced to be sure that the files still appear as you would expect.
Check Size of Mailboxes in Exchange
You can use the Exchange Management Shell to see the size of mailboxes. By viewing the mailbox sizes before and after optimization you'll be able to work out the savings made.
The following will display the TotalItemSize for a mailbox:
Get-MailboxStatistics -Identity firstname.lastname@example.org | select DisplayName,TotalItemSize
To view this data for all mailboxes in a database you can do the following (you need to supply <DatabaseName>):
Get-MailboxStatistics -Database <DatabaseName> | select DisplayName,TotalItemSize
You can get more information on how to use this cmdlet by typing the following in Powershell:
Get-Help Get-MailboxStatistics -examples
Querying the Database Size
Querying the database size will not show you anything useful. This is because optimization will free up space inside the database that can be used again in the future but will not actually reduce the size of the database itself.
So, calls to Get-MailboxDatabase to obtain 'DatabaseSize' and 'AvailableNewMailboxSpace' will not display useful information about reclaimed space following optimization. According to the Exchange Team, 'AvailableNewMailboxSpace' tells you how much space is available in the root tree of the database but does not include free pages within mailbox tables, index tables, etc.
If nothing appears to have been optimized please check the following:
- the emails are old enough to be optimized (any email received within 7 days immediately before the optimization was started is ignored by default).
- the emails have been read (unread mail is currently ignored).
- the extensions of the attachments that you expect to be optimized are supported types and these types have been selected in the File Types dialog.
- if you are expecting hidden content to be removed, check that the rules in the 'Hidden Content' tab of the Settings dialog are set correctly.
If the above checks have been followed then check the report and the log for anything unusual that may have happened during processing.
If anything unexpected happened and you need to get in touch with us, please read about what you need to send us.