migrated email system from POP3/IMAP environment to various on-premise Exchange versions (2003, 2007, 2010, 2013)
upgraded Exchange 2003 organization on singe server to Exchange 2007 organization, including mail store server on Windows 2003 failover cluster, Transport, and Client Server on VM in Widows 2008 failover cluster; smart host in DMZ and continues standby replication to DR site
troubleshot various Exchange issues related to mail flow, security and SPAM control
migrated clients messaging system from POP3/SMTP to Google Apps
migrated clients messaging system from POP3/SMTP to hosted Exchange, Office 365
created centralized PST storage for roaming users using distributed file system
secure mailboxes with various anti-virus, anti-spam solutions from leading vendors
implemented various email backup and archiving schemes