Shared computer, single user account, with multiple discrete log in to Office online app.

Question

Dear everyone,

We have experienced on shared computers (one user account) that the previous log in to Office online (and personal content) is appearing despite a new login with Microsoft Authenticator (new user credentials, same organization).

All the shared computer users have M365 accounts from mainly two organizations. There is no common filesharing server available on the network we are connected to. So, we though it could be neat that they log in to their M365 app of choice, Teams/SharePoint/OneDrive, to send the data files safely to their own storage. However, we see this security hole.. E.g. I log in to my area on office.com with Microsoft Authenticator, but instead get access to the office area belonging to the previous user of the computer (that was there exporting their files the day before). Logging out and back in doesn't help either. The "stay signed in" option was not used.

Any ideas on what we can do to prevent this?

Is Online Office not meant to be used for multiple log ins on the same shared computer?

Is this an Authenticator issue/bug?

Background: The shared computers is connected to medical technical instruments with 50-70 users. The system requires a non-organizational, but instead instrument-vendor purchased computer. All trained users get access to the same user account log in, but need to get the acquired files out of the system somehow. DropBox, Google Drive etc is blocked by the organization on their office computers. We have 10 shared computers and in total 200 users. OS on the computers can be anything from Win7 to Win11. We do not have institutional support for our shared computers, but instead have full admin rights on all.

Hope someone can help :)

Answer 1

Dear Idun Dale Rein,

Thank you for reaching out and providing detailed information regarding the access issues you are experiencing on shared computers with multiple logins to Office Online.

The behavior you're encountering is likely due to browser cache. When multiple users log in with the same user account on a shared computer, the browser may retain session information, which can lead to previous users' data being displayed even after logging in with new credentials.

To mitigate this issue, I recommend using an "incognito" or "private" browsing window for each user. Here are a few benefits of this approach:

1. **Session Isolation**: Incognito window operates independently, meaning that once it is closed, all data from that session—including cookies and cached files—will be cleared. This prevents any previous user's data from being accessible.
2. **User Privacy**: Utilizing incognito mode protects the privacy of each user, ensuring that their login information and personal content remain secure and inaccessible to others.
3. **No Impact on Other Users**: Since the incognito window is separate from the regular browsing session, it will not affect other users' logins or data.

To open a private browsing window, users can typically press Ctrl + Shift + N (in Chrome) or Ctrl + Shift + P (in Firefox and Edge) to quickly access this feature.

Implementing this practice should help resolve the security concerns you've raised. If the issue persists or if you have further questions, please don’t hesitate to reach out.

Thank you for your time and patience, we hope you have a great day!

Sincerely,

Community Moderator | Sophia