Microsoft MS-900 Cheat Sheet: Microsoft 365 Fundamentals

May 1, 2026

Review the retired Microsoft 365 Fundamentals (MS-900) scope, cloud productivity concepts, services, identity, licensing, security, compliance, and current replacement choices.

On this page

MS-900 is a retired Microsoft 365 Fundamentals route. Use this cheat sheet to recognize the older fundamentals scope, then choose the current Microsoft route that matches your real goal.

Use this as a route check. Review the old fundamentals areas, then compare current Microsoft 365, security, Power Platform, and Copilot administration routes.

Open MS-900 replacement page Compare Microsoft 365 routes

Exam snapshot

Field	Detail
Issuer	Microsoft
Retired route	Microsoft 365 Fundamentals
Exam code	MS-900
Current status	Legacy exam guidance
Closest current choices	AB-900, SC-900, PL-900, and Microsoft 365 administrator routes
IT Mastery status	Replacement page with sample questions

Old fundamentals map

Area	What to know	Current route clue
Microsoft 365 services	Teams, Exchange, SharePoint, OneDrive, productivity apps, and admin centers	Use Microsoft 365 admin routes if your goal is operations
Cloud concepts	SaaS, collaboration, availability, service health, and cloud value	Use fundamentals routes if you are new to Microsoft cloud
Identity and access	Microsoft Entra ID, users, groups, SSO, MFA, and basic governance	Use SC-900 or SC-300 depending on depth
Security and compliance	Data protection, retention, DLP, audit, and compliance centers	Use SC-900 or SC-401 depending on depth
Licensing and support	Service plans, subscriptions, service health, support, and lifecycle	Use admin routes if you handle tenant operations
Copilot and agents	Copilot readiness, administration basics, tenant context, and agent concepts	Use AB-900 when Copilot and agent fundamentals are the goal

Must-know distinctions

Distinction	How to decide
MS-900 vs AB-900	MS-900 was Microsoft 365 fundamentals; AB-900 is the newer Copilot and agent administration fundamentals direction.
MS-900 vs SC-900	SC-900 focuses on security, compliance, and identity fundamentals.
MS-900 vs PL-900	PL-900 focuses on Power Platform apps, automation, Dataverse, and business solutions.
Microsoft 365 admin vs fundamentals	Admin exams expect tenant-management decisions, not only product recognition.
Teams vs SharePoint vs OneDrive	Teams coordinates collaboration; SharePoint stores sites and files; OneDrive supports personal work files.
License vs service plan	A license bundle can include multiple service plans; access depends on assignment and enabled services.

High-yield checklist

Confirm whether the old MS-900 code is still your actual target.
If you want Copilot and agent administration fundamentals, compare AB-900.
If you want identity, security, and compliance fundamentals, compare SC-900.
If you want business apps and automation fundamentals, compare PL-900.
If you manage Microsoft 365 tenants, compare MS-102 and related administrator routes.
Know the core Microsoft 365 workloads: Teams, Exchange, SharePoint, OneDrive, Microsoft 365 apps, and admin centers.
Tie user access problems to identity, licensing, service plans, or policy.
Tie data-protection problems to Purview, labels, retention, DLP, and audit concepts.
Tie service outages to service health, tenant settings, or user-specific configuration.

Common traps

Studying the retired MS-900 route when a newer fundamentals page fits better.
Treating Microsoft 365 as one product instead of a suite of workloads.
Confusing identity setup with licensing assignment.
Assuming Teams files are separate from SharePoint storage behavior.
Choosing an administrator-level route when you only need fundamentals.

Practice strategy

Use the MS-900 page as a route translator. If the sample questions feel like broad product recognition, choose a current fundamentals route. If they feel too basic and your real work is tenant administration, move to MS-102, MD-102, MS-700, or another administrator page.

Revised on Monday, May 25, 2026