Dropbox: Collaboratively Edit Microsoft 365 Files (Co-Authoring)

Environment

U-M Dropbox, Microsoft 365

Issue

I would like to collaborate in real-time on Microsoft 365 files stored in U-M Dropbox. Can I do this? If so, how?

Resolution

Yes, you can collaborate in real-time with others on Microsoft 365 files stored in U-M Dropbox using the co-authoring feature. Co-authoring works across Windows, macOS, and on the web, even if each co-author is using a different operating system (OS) or browser.

System requirements

  • macOS users:
    • You should opt in to Dropbox on File Provider to access and use this feature seamlessly. (This requires macOS version 12.5 or later.)
    • If you (or any collaborators who are also on Mac computers) aren’t on File Provider, you’ll still be able to open files for co-authoring from within Word, Excel, and Powerpoint but won’t be able to begin a co-authoring session by opening it from your Finder without creating a new conflicted copy.
      • For example, if you open a file you own from Dropbox in the Finder and then turn on AutoSave to establish co-authoring, it will create a conflicted copy (i.e., adds a “(1)” to the title), delete the old one, and remove any pre-existing direct shares because it is a new file.
  • Windows users: You must be on Windows 10 or later to use Microsoft co-authoring.
  • Your Microsoft 365 apps must be on version 2311 or later and signed in to your U-M Microsoft 365 account for compatibility with co-authoring.
    • If you are a Michigan Medicine affiliate, you will use your HITS-managed (@med.umich.edu) Microsoft 365 account to connect via the desktop apps.

Different experiences between Mac users

The following outlines the different experiences between Mac users who are/aren't on File Provider and who have/haven't enabled co-authoring. These differences do not apply to Windows users. ("File Provider OFF" means you haven't upgraded to File Provider; "Co-Authoring OFF" means you haven't set up co-authoring in your Microsoft apps.)

  • File Provider OFF, Co-Authoring ON
    • When you open a Dropbox file from a Microsoft 365 app, AutoSave is ON and co-authoring is automatically available.
    • When you open a Dropbox file from Finder, AutoSave is OFF, and co-authoring is not automatically available.
      • Turning AutoSave ON creates a conflicted copy (i.e., a new file with “(1)” in the title), deletes the original file, and removes all direct shares. However, co-authoring is now available on the new copy with AutoSave ON.
  • File Provider OFF, Co-Authoring OFF
    • Co-authoring can only be done via Dropbox on the web and Microsoft 365 Online through the browser.
  • File Provider ON, Co-Authoring OFF
    • You won’t be able to open a co-authoring file locally to edit. You will be prompted to log in to "Dropbox for Teams" and, if you do not log in, will receive a “Can’t Open File” error.
    • Co-authoring can only be done via Dropbox on the web and Microsoft 365 Online through the browser.
  • File Provider ON, Co-Authoring ON
    • When you open a Dropbox file from a Microsoft 365 app or Finder, AutoSave is ON, and co-authoring is automatically available.

Getting started

On desktop

To use the co-authoring feature on your desktop, you must add Dropbox as a cloud storage location in Microsoft 365. You need to do this for each device on which you want to enable co-authoring.

  1. Open Microsoft Word, PowerPoint, or Excel on your desktop.
  2. Click Open in the left sidebar. 
  3. Click Add a Place (Windows) or Manage Storage Accounts (Mac).
  4. Select Dropbox for Teams.
  5. Enter your @umich.edu email address and click Continue with single sign-on.
  6. Log in with your uniqname and UMICH password via U-M Weblogin.

Refer to the Dropbox Help Center for detailed instructions with screenshots on setting up co-authoring on your computer. Dropbox also offers an interactive walkthrough experience.

On the web

To use co-authoring on the web (via dropbox.umich.edu):

  1. Log in to U-M Dropbox.
  2. Hover over the Word, Excel, or PowerPoint file you want to open and click the three-dot (...) icon.
  3. Hover over Open in and select Word/Excel/PowerPoint for the web from the drop-down menu.
  4. Ask the people you'd like to collaborate with to follow the same steps.
  5. The file will open in your browser using the Microsoft 365 Online integration. You can then edit it in real time with others.
    • You may be prompted to log in to your Microsoft 365 account. Log in to either your ITS-managed or HITS-managed account, depending on the type of data you're editing and your affiliation. Remember to follow the appropriate guidelines for editing PHI using this integration (i.e., only when logged in to your Michigan Medicine account).
  6. Click the file title in the top left and select Save and return to Dropbox when you're finished editing.

Tip: If you encounter issues with collaborators accessing and editing the file in real time via Microsoft 365 Online, try moving the file to a shared folder and sharing the folder with the collaborators.

Important things to note

  • The AutoSave toggle in the top left of the Microsoft 365 app should be turned on automatically the first time you start a co-authoring session. (For Mac users, this requires File Provider.) If you’re working on a new file, you may need to turn on this toggle yourself. Co-authoring sessions won’t work if the AutoSave toggle is turned off.
  • Individuals who do not have co-authoring set up on their desktop won’t be able to open a co-authoring file locally to edit. They will be prompted to log in to Dropbox for Teams, and if they do not log in, they will receive a “Can’t Open File” error.
  • You can collaborate externally with co-authoring, but individuals outside U-M Dropbox will need to use Microsoft 365 Online via Dropbox on the web. This requires a Dropbox account and direct access to the files being co-authored.
    • If they do not have a Dropbox account or don’t have access to co-authoring on the web, they can only open a “view-only” copy.
  • Supported file types include:
    • On desktop: .docx, .pptx, .xlsx, .xlsm
    • On the web: .docx, .pptx, .xlsx
  • Dropbox Badge will no longer appear once you’ve enabled co-authoring.
  • You can open files up to 500MB in the Microsoft 365 apps via Dropbox. However, if you open a file that’s larger than 500MB from File Explorer (Windows) or Finder (macOS), it’ll open in offline mode and prevent co-authoring.
  • If you encounter issues opening files directly from File Explorer or Finder, try opening the files within the Microsoft 365 apps to initiate co-authoring.
  • As a reminder, you can't open or edit password-protected Microsoft files in Dropbox.
  • To open files locally without starting a co-authoring session, you can either: 
    • Lock the file before opening it.
    • Toggle off AutoSave in the top left of Word, Excel, or PowerPoint after opening the file.
  • You can view your name and the names of other collaborators who have the file open simultaneously at the top of the file. You'll also notice a bubble with their initials when they're editing the file while you're working on it.
  • Changes you make will be saved automatically to your U-M Dropbox account.

Common questions

Why are there conflicting copies or syncing issues when co-authoring with others?

  • If not all collaborators have co-authoring enabled, it can lead to conflicting copies, syncing issues, or the document freezing. This happens when one or more people don’t have AutoSave turned on, which is required for co-authoring to work smoothly.
  • To check if co-authoring is enabled:
    1. Open the file in Word, Excel, or PowerPoint.
    2. Look at the top left of the window for the AutoSave toggle.
    3. If AutoSave is off, toggle it on to enable co-authoring.
  • Once everyone has AutoSave enabled, changes will sync automatically, and you should no longer encounter conflicts or freezing issues.

Why am I seeing a “Protected view” warning when opening Dropbox files on Windows?

  • You might see this warning because Dropbox is considered an untrusted source by default, and Windows automatically opens files from untrusted sources in view-only mode for security reasons.
  • You’ll see a banner at the top of your screen warning that files from the internet could contain viruses. Click Enable editing in the banner to start editing the file.

Additional Information

  • For users who are missing the Open in button, Dropbox has a troubleshooting article that describes the issue.
  • You and your collaborators who are co-authoring a shared Microsoft file should refrain from downloading the file and editing it using a local Microsoft 365 app, as re-uploading the file will break the ability to edit the file using Microsoft 365 Online. You may encounter an error: "Sorry, this document can't be opened for editing."
    • This issue can be corrected by reverting the file to a previous version before the file was re-uploaded.
  • Dropbox Help Center article on co-authoring
  • Learn more about document collaboration and co-authoring from Microsoft.

Need additional information or assistance? Contact the ITS Service Center.

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