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420 Tenants. One Secure Email Environment
After years of acquisition, a national services enterprise network needed to consolidate 420 email tenants and more than 25,000 mailboxes. Over 9 months, The DORIAN Group brought more than 1,300 locations into one secure, shared environment, on time and on budget.
Client
Enterprise Network
Services
Email Migration
On This Page
The Challenge
Our Approach
The Outcome
The Challenge
Acquisition growth had left the network with 420 separate companies across locations in the U.S. and Canada. The case for one shared environment was clear. The path there was not.
Each location had its own teams, tools, and business logic. A uniform cutover plan might work on paper, but it would not account for the differences between source tenants or the realities of each location. The network needed a program that could repeat the right core process while making room for local needs.
Our Approach
The DORIAN Group began by mapping every source tenant to the future shared environment. That work created a reliable starting point for migration planning and surfaced the local logic that needed to carry forward.
The first week included 5 migrations. Rather than treating those early conversions as a proof of concept, the team used them to test the operating model: What did each location need? Where did communications fall short? Which issues could be solved before the next wave?
Those lessons informed the next wave. The program soon scaled to 10 to 20 migrations each week, with data engineering, change management, communications, and post-migration support moving together. The result was a program designed to get faster without becoming less responsive.
Training Designed for a Busy Workday
The migration would only work if people could understand what was changing and act on it without stepping away from their day. The DORIAN Group worked with the client's internal communications team to create 62 resources for leaders, managers, and staff.
Not every message belonged in a long email. Short videos and site signage made the key actions easy to find. Detailed PDFs and a SharePoint hub gave people somewhere to turn when they needed more. The team adjusted the mix as staff feedback came in, keeping support useful instead of simply increasing the volume of communications.
Support at Cutover
The DORIAN Group checked in with each location on conversion day and stayed close through early support. Those conversations gave local teams a clear place to turn for help and gave the program team direct visibility into what needed attention in the next wave.
Map
Mapped the business logic in 420 source tenants into one shared destination.
Migrate
Used each early conversion to improve the next, then scaled to 10 to 20 migrations per week.
Communicate
Created 62 role-specific resources, including videos, PDFs, signage, and SharePoint content.
The Outcome
All 420 tenants and more than 25,000 mailboxes moved into a shared environment on time and on budget. Every client success metric finished green, and the project closed without delays or problems requiring senior escalation.
The work gave the network more than a consolidated email environment. Client leadership asked The DORIAN Group to share the delivery framework so it could inform future technology programs across the organization.
“The DORIAN Group’s combination of diligence and empathy ensured on-time delivery with a proactive helping hand.Little touches like day-of check-ins and donuts on conversion day helped the teams get through the conversion day with a smile on their faces.”
VP, Enterprise Transformation · National Enterprise Network