Essex Property Trust Relocates from a Diverse Email Environment to the Microsoft Office 365 Cloud


“Binary Tree’s Exchange Pro and our consulting partner Hott Solutions allowed us to take an email migration project that was at a standstill and finish it in a very short period of time.”

— Sam Ghnaim, Acting Director of IT, Essex Property Trust


The Decision to Move to the Microsoft Cloud

Essex Property Trust manages 180 residential rental properties from multiple offices in California and Washington State. The company wanted to open new collaboration opportunities for employees across the company, while moving to the cloud services of Microsoft Office 365 in order to standardize its applications.

One of the company’s key objectives was to eliminate the multiple versions of Microsoft Exchange and the on-premises servers used for its corporate email system. This complex Exchange environment, which encompassed Exchange 2003, 2007, and 2010 servers, presented many business and technical challenges, including significant downtime and difficulty in managing, troubleshooting, and making changes in the system.

Challenges to the Migration

Initially, Essex’s IT staff attempted to migrate its mailboxes with Microsoft’s Exchange Management Console. However, this do-it-yourself approach required multiple steps to manually migrate each mailbox through the different Microsoft Exchange versions before they could be migrated to Office 365. After nearly 18 months of trying this approach, Essex had migrated only 125 mailboxes out of 1,200 total

Another challenge was very large mailbox sizes, as Essex had not previously implemented policies on message retention and mailbox size limitations. Any attachments that exceeded the Office 365 limit of 25GB had to be found and stored in separate repositories before the mailboxes could be moved, thus adding to the prolonged migration time-frame.

Finding a Better Way to Migrate

Given these challenges, it became clear that Essex needed an automated solution as well as expertise in Exchange migrations. The company’s IT staff contacted their longtime consulting firm, Hott Solutions, which recommended Binary Tree’s Exchange Pro software after a thorough evaluation of migration products. To complement the choice of Exchange Pro, Hott Solutions also selected the Mail Attender product from Sherpa Software to assist with preparing the environment for the migration.

Preparing the Mail Environment for the Migration

Hott Solutions used the Mail Attender product to perform an in-depth analysis of the mailbox data prior to the migration. Mail Attender identified the mail attachments that exceeded Office 365’s 25GB limit and enabled the team to remove them from mailboxes and store them in separate repositories for future access.

Accelerating the Migration with an Automated Solution

Exchange Pro migrated mailbox data from the Microsoft Exchange platforms to Office 365, automated user scheduling and notifications, and provided tools for managing all migration tasks. User mailboxes in the corporate office were migrated first, then mailboxes for the company’s individual properties were grouped into regions for migration scheduling. By using the Binary Tree products, the migration of 1,100 mailboxes (with an average size of 10GB) was completed within two months.

“Binary Tree’s Exchange Pro and our consulting partner Hott Solutions allowed us to take an email migration project that was at a standstill and finish it in a very short period of time,” says Sam Ghnaim, Acting Director of IT for Essex. “We wouldn’t have had a successful migration without the Binary Tree software and the additional assistance of Hott Solutions.”

The Benefits and Results

In addition to a faster migration, Essex realized other benefits from using Binary Tree’s products:

Flexibility for migration scheduling

Binary Tree’s Web portal for managing migration activities and scheduling in Exchange Pro helped the migration stay within the specified Office 365 bandwidth and the scheduled time windows.

Mailbox cleanup

With Mail Attender’s ability to identify very large mailboxes and attachments, the migration team performed some long-needed cleanup. This action led Essex to develop a corporate policy on email retention.

Minimal user impact

Users automatically received emails with customized details about their scheduled migration. “Exchange Pro's capabilities for automating user communication were a huge benefit for us because we were doing the migration with a very small team,” says Ghnaim. And because the users experienced very minimal downtime, they gave positive feedback on the migration process.

Reports for corporate managers

The status reports produced by Exchange Pro provided the information for clear status reports to the migration team and company managers.

Simpler, more manageable email environment

Before, the email environment at Essex was very complex due to the different Exchange systems. This design generated excessive network traffic and was difficult to manage. Today, a single Microsoft Exchange 2010 environment at the Essex data center directly synchronizes with the Office 365 cloud for simpler connectivity and management.

Ability to take full advantage of Office 365

With the mailboxes migrated to Office 365, Essex can turn its attention to leveraging this platform to meet its business goals of improved communications and collaboration among employees.


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