Mailbox Delegation in Office 365 for Small Business

The Small Business plans do not explicitly provide access to the EAC.  But you can do this by appending the correct EAC URL in your browser:

http://community.office365.com/en-us/wikis/exchange/4077.aspx

Info on how to set delegated mailbox access is here:

http://blogs.office.com/2013/09/04/configuring-delegate-access-in-outlook-web-app/

http://support.microsoft.com/kb/2572646

http://technet.microsoft.com/en-us/library/ff522363(v=exchg.150).aspx

For ongoing support please contact the Microsoft Support team per:

http://office.microsoft.com/en-nz/help/contact-support-for-technical-presales-billing-and-subscription-issues-HA103836042.aspx?redir=0

Outlook Performance and Mailbox Size or Item Count

Mailbox size or item count can have a serious effect on the performance you see in Outlook. The following article gives some good insight into why, and what can be done about it.

http://blogs.technet.com/b/exchange/archive/2005/03/14/395229.aspx

References:
http://blogs.technet.com/b/exchange/archive/2005/03/14/395229.aspx

Get Exchange Mailbox Stats

Get-MailboxStatistics

Get-MailboxStatistics | ft DisplayName,TotalItemSize,ItemCount

Get-MailboxStatistics | Sort-Object TotalItemSize –Descending | ft DisplayName,TotalItemSize,ItemCount

References:
http://www.msexchange.org/articles-tutorials/exchange-server-2007/management-administration/getting-mailbox-statistics-exchange-2007.html