Skip to main content
25+ TB migrated
99.996% item-level accuracy — zero downtime

Migrate to Microsoft 365

4TH AND BAILEY has migrated over 133,675 email items and 33.64 GB of data in a single engagement with zero downtime and 99.996% item-level accuracy. Email migration is not technically complex — it is operationally complex. Getting it wrong means lost data, disrupted workflows, and user trust that is difficult to rebuild.

Every migration begins with a pre-migration audit: mailbox inventory, size analysis, special folder identification, shared mailbox and distribution list mapping, and a cutover plan that minimizes disruption to business operations.

Migration source systems supported include on-premises Microsoft Exchange (all versions), Google Workspace (Gmail), IMAP-based email systems, Microsoft 365 tenant-to-tenant, and hosted Exchange platforms.

Post-migration, every Exchange Online deployment is configured with CISA SCuBA anti-phishing baselines, DMARC/DKIM/SPF alignment, and Exchange Online Protection tuning before users are cut over. Mail flow is verified before the source system is decommissioned.

What is included

  • Pre-migration mailbox and data audit
  • Migration project plan and cutover schedule
  • Source-to-destination data migration (email, calendar, contacts)
  • Shared mailbox and distribution list migration
  • DMARC/DKIM/SPF DNS configuration
  • Exchange Online Protection and anti-phishing configuration
  • User communication and cutover guidance
  • Post-migration verification and issue resolution