Microsoft 365 Migration Assumptions Log
This is a practical guide to building a assumptions log for a microsoft 365 migration project — a register of the assumptions the plan depends on, to be validated, adapted to the realities of migrating email, files and collaboration to Microsoft 365.
What a Assumptions Log is
A assumptions log is a register of the assumptions the plan depends on, to be validated. For the full concept and how it works in general, see Project Assumption. On a microsoft 365 migration project it plays the same role, tuned to this kind of work.
Why it matters for a Microsoft 365 Migration project
Microsoft 365 Migration projects live or die on migrating email, files and collaboration to Microsoft 365. A well-built assumptions log gives the team a shared, explicit reference for exactly that — reducing ambiguity, aligning stakeholders, and making problems visible early enough to act. Skipping it, or doing it generically, is how microsoft 365 migration projects drift into avoidable delay and cost.
What to include
- Assumption
- Impact if wrong
- Owner
- Validation status
Microsoft 365 Migration-specific considerations
Tailor the assumptions log to the risks that most often derail microsoft 365 migration projects:
- Mailbox and file migration errors
- User adoption and training
- Security and compliance configuration
Example
On a real microsoft 365 migration project, the assumptions log would be shaped by migrating email, files and collaboration to Microsoft 365. In particular, it should explicitly account for the project’s biggest risks — mailbox and file migration errors, user adoption and training, security and compliance configuration — rather than treating them as afterthoughts.