X-ELIO, a global solar energy developer, has successfully transitioned more than 350 employees across nine countries and four continents to a Microsoft 365-based digital workplace, completing a complex migration that swept away 6 terabytes of legacy Google Drive data. Executed in partnership with NTT DATA, the project stands out for its rigorous governance framework and a change-management playbook that turned a potentially disruptive IT overhaul into a model of user adoption.
Migrating a multinational workforce from one productivity ecosystem to another is never just a technical lift-and-shift. It demands rethinking collaboration habits, establishing ironclad security policies, and persuading hundreds of professionals — each with their own workflows — that the new platform will make their daily jobs easier, not harder. For X-ELIO, the stakes were especially high: the company operates solar plants across continents, requiring seamless communication between on-site engineers, project managers, and C-suite executives.
The move, completed in mid-2024, saw X-ELIO replace its fragmented Google Workspace environment with the integrated stack of Microsoft 365, including Teams, SharePoint Online, OneDrive for Business, and Exchange Online. NTT DATA designed and implemented a phased rollout that kept business disruption to a minimum while enabling IT teams to identify and purge redundant, outdated, or trivial data from 6 terabytes of Google Drive content — a digital spring cleaning that would reduce future storage costs and simplify information governance.
A Governance-First Migration Strategy
Governance was not an afterthought; it was the project’s backbone. From the outset, X-ELIO and NTT DATA established a comprehensive governance framework that dictated how information would be classified, protected, and retained within the Microsoft 365 environment. This included defining which data would migrate, who could share what externally, and how to enforce compliance with GDPR and other regional regulations across nine country jurisdictions.
The migration team created a detailed data mapping between Google Workspace structures and Microsoft 365 groups, teams, and site collections. Rather than replicating the old folder hierarchies blindly — which often bury governance issues — they designed new information architectures based on business functions, projects, and teams. Every migrated folder was tagged with metadata for automated retention and sensitivity labels, ensuring that from day one, employees were working within a compliant framework.
One of the most crucial decisions was to use a phased migration by business unit rather than a big-bang switchover. This allowed the governance team to validate policies on a smaller pilot group, refine the automated classification rules, and train champions within each department who could later assist their peers. It also gave IT the bandwidth to address any security or permission errors before they rippled across the entire organization.
Cleaning 6TB of Data: The Pre-Migration Cleanup
Before a single byte was moved, X-ELIO undertook a massive data hygiene initiative. An analysis of the company’s Google Drive revealed that a significant portion of the 6 terabytes consisted of duplicate files, outdated drafts, personal photos, and content long past its retention schedule. Migrating all that would not only waste time and resources but also clutter the new Microsoft 365 environment and confuse users.
NTT DATA deployed automated tools to scan and classify content, identifying files that hadn’t been accessed in over two years, items owned by departed employees, and assets that violated naming conventions or security policies. Business managers were then engaged to decide what to keep, archive, or delete. The cleanup reduced the total migration footprint, lowered the risk of inadvertently exposing sensitive information, and provided an immediate lesson in data stewardship that would underpin future governance training.
This step also uncovered shadow IT risks — shared drives that had grown organically without proper ownership or access controls. By addressing these before migration, X-ELIO avoided replicating a messy permission structure into Microsoft 365. Instead, every site and team was provisioned with clear ownership, guest access controls, and audit logging enabled from the start.
Change Management and Adoption Playbook
Technology alone does not drive adoption. NTT DATA and X-ELIO co-developed a change management playbook that placed communication, training, and support at the heart of the project. The playbook recognized that employees across nine countries would have varying levels of digital literacy, different language needs, and distinct cultural attitudes toward new technology.
The adoption program began months before the first migration wave, with executive sponsors openly championing the move. Town halls, email campaigns, and intranet posts spelled out the benefits: better collaboration through Teams, reliable email via Exchange, and a single place for documents in SharePoint. Crucially, the messaging didn’t just focus on the tools — it highlighted how these tools would solve real pain points, such as the confusion caused by multiple Google Drive folders with overlapping permissions.
Training was delivered in multiple languages and tailored to job roles. Field engineers received quick-reference guides on using Teams via mobile devices to report plant status, while legal and finance teams underwent deep-dive sessions on sensitivity labels and data loss prevention policies. A network of “M365 Champions” — one or two per office — acted as first-line support, answering colleagues’ questions and demonstrating best practices. These champions also fed back to the project team, enabling continuous improvement of training materials and addressing common frustrations in near-real-time.
Post-migration, adoption metrics were tracked using Microsoft 365 usage reports and Viva Insights, with regular pulse surveys measuring user satisfaction and productivity perception. The data showed that within three months, average daily Teams usage had surpassed the previous peak usage of Google Chat, and SharePoint Online became the default destination for document collaboration, largely eliminating the sprawl of unmanaged drives.
Technical Execution and Lessons Learned
The technical migration itself was handled through a combination of vendor tools and custom scripting, ensuring data fidelity and metadata preservation. NTT DATA orchestrated the move in waves, starting with a pilot group of 30 users during a low-activity period. This pilot uncovered several edge cases, such as Google Drive files with extremely long paths that exceeded SharePoint Online’s limit, and embedded Google Workspace links inside documents that would break after the cutover.
To solve these, the team implemented pre-flight checks that flagged problematic files, allowing remediation either by the user or by automated scripts that shortened paths and updated internal links. For email migration, IMAP-based sync was used to transfer Gmail messages, labels, and contacts to Exchange Online, with a special focus on preserving large attachments and calendar integrations. The entire user base was cut over across four major waves spanning eight weeks, with each wave benefiting from the lessons of the previous one.
One critical takeaway was the importance of maintaining a hybrid coexistence period. During each wave, X-ELIO kept both Google Workspace and Microsoft 365 environments running side by side, with mail routing handled by central transport rules. This ensured that communication between migrated and non-migrated users remained seamless, and it gave users who were struggling an extra week to acclimate before their old accounts were disabled.
Security and Compliance in a Multi-Country Setting
Operating across nine countries meant X-ELIO had to navigate a patchwork of data residency and privacy regulations. The governance framework leveraged Microsoft 365’s compliance center to set per-location policies. For example, data for European employees was automatically held within EU data centers using multi-geo capabilities, while specific retention schedules were applied based on local legal requirements.
Conditional Access policies were rolled out to enforce multi-factor authentication for all users, with additional controls for access from unmanaged devices or high-risk locations. Azure Information Protection labels were integrated into the default document libraries, so that any file saved in a protected project site would inherit encryption and access restrictions automatically. This policy-driven approach meant that even if a user made a mistake, the system would prevent data from leaking outside the organization.
Regular audits were baked into the governance model from the beginning. NTT DATA set up automated Compliance Manager assessments and weekly reports for the IT security team, ensuring that any configuration drift — such as a SharePoint site made public by accident — was detected and corrected within hours.
Measuring Success: Business Outcomes
The true measure of any migration is not just uptime but how the business operates afterward. X-ELIO reported a notable increase in cross-border collaboration efficiency. Teams that previously relied on disjointed email threads and shared drives now used Microsoft Teams channels integrated with Planner and OneNote, reducing the time spent searching for information by an estimated 20%. The cleanup of 6TB of data also translated into lower storage costs and easier e-discovery, as legal teams could now locate and hold relevant documents for contracts and regulatory reviews without wading through years of digital clutter.
From an IT perspective, support tickets related to collaboration tools dropped significantly after an initial post-migration spike, which was expected as users adjusted. The centralized admin console and unified security dashboard allowed the small internal IT team to manage the entire global environment more effectively than they ever could with Google Workspace’s decentralized admin model.
Perhaps most tellingly, the playbook that emerged from this project — covering governance, migration, and adoption — is now being used as a template for other mid-sized multinationals looking to move to Microsoft 365. NTT DATA and X-ELIO presented the case at several industry webinars, with audience members particularly interested in the data cleanup methodology and the champion network approach.
Best Practices for Future Migrations
For CIOs and IT leaders considering a similar move, X-ELIO’s experience offers a clear set of best practices. First, treat governance as a prerequisite, not an afterthought. Define your information architecture, compliance policies, and security controls before the first data packet moves. Second, invest heavily in change management — technology training is not enough; you need to win hearts and minds by connecting the new tools to better business outcomes. Third, never skip the data cleanup; migrating garbage simply digitalizes chaos. Finally, embrace a phased approach with real coexistence, allowing users to learn and adapt without pressure.
As more companies accelerate their digital transformation efforts, the X-ELIO story demonstrates that with the right partners and a disciplined playbook, a global Microsoft 365 migration can be more than an IT project — it can become a catalyst for a more connected, productive, and secure organization.