Lesson 2: Where a File Belongs: OneDrive, Teams or SharePoint

Why this matters

In Level 1 you checked which plan you have and what your IT team may have switched off. Next comes the question people get wrong most often: where should this file live? If you choose badly, files get lost when someone leaves, people work on duplicate copies, and documents get shared too widely. This level gives you a model of how the pieces connect and a three-question rule for deciding.

Plan note: This lesson needs a work or school account that includes SharePoint and Teams, such as most Microsoft 365 Business and Enterprise plans. Consumer plans (Microsoft 365 Personal or Family) include OneDrive but have no SharePoint sites or team channels. If you are on a consumer plan, read along and do the OneDrive parts only.

The model: three front doors, two kinds of storage

Think of a single filing building with different entrances:

1. OneDrive (work or school) is your personal work storage. It is your own desk drawer. You own the files, and nobody else sees them unless you share them.
2. A SharePoint site is a shared team storeroom. Its files sit in a document library that belongs to the team or project, not to any one person.
3. A Teams channel has no storage of its own. It is a front door into a SharePoint site. Every team has a connected SharePoint site behind it.

How Teams uses SharePoint:

• Standard channels: each channel's files tab opens a folder named after the channel inside the team site's default document library. The General channel gets a folder too.
• Private and shared channels: each one gets its own separate SharePoint site, which only that channel's members can open. Its files tab opens that site's default library.
• Chat files (one-to-one or group chats) work differently. A file you attach in a chat is stored in your OneDrive, in a folder called Microsoft Teams Chat Files, and shared only with the people in that chat. If you leave the organisation, those files leave with your OneDrive. This is a common reason team files go missing.

Screen note (checked November 2026): Microsoft has renamed the channel Files tab to Shared. The tab now has an In library view, which is the SharePoint folder, and an In posts view, which lists files and links shared in channel posts. Some tenants may still show Files. They are the same thing.

The three-question rule

Ask these questions in order for any file:

1. Who owns it? If only you do (a draft, your notes, a personal CV), use OneDrive. If a team or project owns it, use shared storage.
2. Who needs it? If your working team needs it day to day, use the Teams channel for that work. If a wider audience needs to read it but not discuss it (policies, templates, finished reports), use a SharePoint site, often a communication or department site.
3. How long must it last? If it must outlast you in your role, it must not stay in OneDrive. Put it in a channel or site, because those belong to the organisation and survive staff changes.

Worked examples:

• Your first rough draft of a proposal → OneDrive. Move it to the channel once the team needs it.
• The live project plan your four-person team edits weekly → the project's Teams channel.
• The company expenses policy everyone reads → a SharePoint site.
• A contract that must be kept for six years → a channel or site, never OneDrive.
• A spreadsheet you dropped into a group chat that turned into team work → it is currently in your OneDrive. Upload it to the channel instead.

Task 1: Sort five of your own files

Do this now:

1. List five real work files you touched this week.
2. For each one, write down your answers to the three questions: owner, audience, lifespan.
3. Mark each one OneDrive, Channel (name it) or Site (name it).
4. Circle any file whose current location disagrees with your answer. Do not move anything yet. Level 4 covers moving files safely.

Task 2: Prove a channel file is one copy

You will open the same file through three doors and confirm that a change made in one shows up in the others.

Desktop or web Teams:

1. Open a team and a standard channel you belong to.
2. Select Shared (or Files) at the top of the channel, then choose the In library view if you see it.
3. Upload or create a small test document, for example Test-single-copy.docx.
4. Open it, type one line ("Edited in Teams"), and close it.

SharePoint on the web:

5. In the same Shared/Files tab, choose Open in SharePoint. Your browser opens the team's site.
6. Notice that you are in the document library, inside a folder with the channel's name.
7. Find the test file and check its Modified time and Modified by. They should match your edit.
8. Open the file in the browser and confirm your line is there. Add a second line ("Edited in SharePoint").

Mobile:

9. In the Teams mobile app, open the same channel and tap its Shared/Files area. Alternatively, in the OneDrive mobile app signed in with your work account, open Libraries and choose the team site.
10. Open the test file. Both lines should be there.

What this proves: there was never a copy. Teams, SharePoint and mobile are three views of one file in one library. If you see different content, it is usually a delay; refresh and check again.

Clean up: delete the test file when you have finished. Recovery is covered later in the course.

Key takeaways

• OneDrive (work or school) is personal work storage; SharePoint sites hold shared, organisation-owned files.
• A standard channel's files are a folder in the team's SharePoint document library. Private and shared channels each have their own site.
• Files attached in chats are stored in the sender's OneDrive, in Microsoft Teams Chat Files.
• The channel Files tab is now called Shared, with In library and In posts views.
• Use the three questions to choose a home: who owns it, who needs it, how long it must last.
• Opening a channel file in Teams, SharePoint or mobile shows the same single copy.