Google Workspace to M365 Migration: Ultimate Guide | Coherence, Inc.

The Ultimate Cross-Platform Cloud Migration Guide: Google Workspace to Microsoft 365 & M365 to Google Workspace

At-a-Glance Migration Tool Comparison

Direction 1: Google Workspace to Microsoft 365 Migration

Option A: The Microsoft Native Tools Path

• • Core User Mailbox Migration (Gmail, Contacts, Calendar): The EAC uses an automated Google Workspace migration wizard. Our engineers configure a secure Google Cloud Service Account and enable the Google Admin SDK to securely pull mailbox data directly into Exchange Online using customized CSV identity mapping lists.
  • Shared Calendars & Resource Mailboxes: The automated native wizard moves primary personal calendar data. However, managed resource calendars (like conference rooms and equipment) must be designated as specific Resource Mailboxes inside the migration batch. Coherence, Inc. manually re-applies complex cross-user permissions and delegation rights post-migration to prevent access gaps.
  • Google Shared Drives to SharePoint Online: Moving files requires switching over to the Microsoft 365 Migration Manager. We install the native migration app in the Google Workspace Marketplace to link environments, scan the Shared Drives for errors, and map each Google Shared Drive to a corresponding SharePoint Team Site Document Library.

Option B: The CloudM Migrate Path

• • Unified User Workload Migration: Identity mapping is controlled through one centralized dashboard. Our engineers run a comprehensive pre-migration scan via CloudM to locate orphaned files, broken permissions, or storage overflows before data ever moves.
  • Automated Shared Calendars Permissions: CloudM Migrate excels at keeping complex sharing permissions intact by preserving the Access Control Lists (ACLs) of secondary and shared calendars. We process calendar links as distinct resource entities, automatically updating user access levels so no post-migration re-sharing is required by users.
  • Shared Drives to SharePoint Integration: Google Shared Drives are mapped side-by-side with user mailboxes in the same migration window. We copy file trees perfectly while mapping Google file permissions directly to their Microsoft 365 security equivalents, preserving structural metadata.

Direction 2: Microsoft 365 to Google Workspace Migration

Option A: The Google Native Tools Path

• • Core User Mailbox Migration (Exchange Online to Google Workspace): For smaller teams, we connect Google Admin’s built-in DMS to Exchange Online via OAuth or tenant impersonation to pull emails. For enterprise moves, our team deploys the advanced Google Workspace Migrate infrastructure on self-hosted Windows Server VMs to extract Exchange mailboxes, personal contacts, and calendar data via the Microsoft Graph API.
  • Shared Calendars & Room Resources: We discover and migrate Microsoft Resource Mailboxes into Google Calendar Resources. Shared calendar delegation rights and secondary calendar permissions are mapped strictly using CSV identity rules to maintain executive assistant scheduling workflows.
  • SharePoint Online to Google Shared Drives: Using the Google Workspace Migrate infrastructure, Coherence, Inc. maps SharePoint Document Libraries and OneDrive for Business accounts directly to Google Shared Drives. We remediate deeply nested or broken inheritance structures in SharePoint prior to the transfer to prevent data loss.

Option B: The CloudM Migrate Path

• • Exchange to Google Workspace Mail Processing: We authenticate via Microsoft Graph API and seamlessly push data into Google Workspace. CloudM handles the structural conversion gracefully, converting rigid Outlook folder hierarchies into flexible Google Workspace Labels.
  • Automated Calendar Access Mapping: The platform maps Exchange calendar permissions directly to Google Calendar ACLs. We automate the transition of shared calendars, ensuring that executive assistants, team leaders, and project managers retain access to critical schedules immediately upon cutover.
  • SharePoint to Shared Drives Optimization: SharePoint Document Libraries and OneDrive accounts are processed in the same interface as mailboxes. Coherence, Inc. uses CloudM to automatically flatten deeply nested SharePoint structures that violate Google Drive’s folder depth best practices, translating SharePoint permissions directly into Google Shared Drive roles (Manager, Content Manager, or Contributor).

Enterprise Cloud Data Migration Challenges Mitigated by Coherence, Inc.

• The “Label” vs. “Folder” Conflict:
  • • Google to Microsoft: A single email in Google can have multiple labels. When mapped to Microsoft’s folders, that item duplicates into every corresponding folder, bloating your M365 storage footprint.
    • Microsoft to Google: Outlook folders become Google labels. If an item is in a nested folder, Google creates a hierarchical label (e.g., Invoices/2026). Coherence, Inc. customizes data deduplication policies to optimize storage post-migration.

• File Name Quirks & Path Length Limits: Microsoft SharePoint Online and OneDrive strictly forbid certain special characters (like *, :, ?, \) and enforce path length limits. Google Drive is highly permissive with characters and allows duplicate file names in the same folder. Coherence, Inc. runs automated pre-migration scrubbing scripts to clean file titles and shorten paths before they break in transit.
• Calendar Interoperability & Recurring Meetings: Recurring meeting series featuring complex exception rules (e.g., “every Tuesday except holidays”) rarely migrate perfectly between Exchange and Google. We provide targeted remediation strategies and automated user notices to ensure team schedules remain intact.