How to Prevent Outlook on the Web Auto Sign-In on Shared Computers
Question details
Users need to stop Outlook on the Web (OWA) from automatically logging into the previous user's mailbox on a shared computer.
- Product
- Outlook on the Web
- Device & OS
- Windows
- Scenario
- Multiple people are using a shared computer with a generic Windows account to access their individual Microsoft 365 emails.
- Observed behavior
- Outlook on the web automatically opens the previous user's mailbox due to persistent browser sessions and active single sign-on (SSO) credentials.
Ensure you have administrator privileges on the shared Windows computer, as you will need to manage user accounts to properly isolate browsing sessions.
Create Separate Windows User Profiles
The most secure and effective way to prevent auto sign-in issues on shared computers is to assign each person their own Windows profile. This completely isolates browser data and cached credentials.
When multiple users share a single generic Windows account, their browser cookies, session states, and single sign-on (SSO) tokens are merged. This is why private or incognito browsing often fails to permanently resolve the issue.
Creating an individual Windows profile for each user ensures that Microsoft 365 credentials remain separated and private.
Log into the shared computer using an administrator account. Click the Start menu and select 'Settings' (the gear icon).
In the Settings menu, click on 'Accounts', then select 'Family & other users' (or 'Other users' depending on your Windows version) from the left sidebar.
Click the 'Add someone else to this PC' button. Follow the on-screen prompts to create a new profile. Repeat this process for each person who needs access to the computer.
Instruct all users to sign in to their dedicated Windows profile before accessing Outlook on the web, and remind them to completely sign out of Windows when they are finished.
Manually Sign Out and Configure Browser to Clear Cookies
If creating individual Windows profiles isn't immediately possible, you must configure the shared browser to clear session data upon closing and manually sign out every time.
Upgrade Your Shared Computer Productivity with WPS Office
While resolving Outlook web login conflicts on shared computers, you may also need a reliable, low-resource office suite for your documents. WPS Office is a free, lightweight, and highly compatible alternative to Microsoft Office, offering Word, Excel, PowerPoint, and PDF tools in one seamless application.
Frequently Asked Questions
Why does Outlook on the web keep signing me in even if I closed the browser?
Modern browsers often save session cookies or use your active Windows Single Sign-On (SSO) credentials to automatically authenticate your Microsoft 365 account. If you just close the window without explicitly signing out or clearing cookies, the session remains active for the next person.
Does using Incognito or Private Browsing mode fix the Outlook auto sign-in issue?
Not consistently. While private browsing prevents saving new cookies, if the computer uses a generic Windows account tied to a Microsoft 365 identity, SSO might still trigger an automatic login. Creating separate Windows user profiles is the most reliable solution.
How do I stop Microsoft Edge from using my Windows account to sign into Outlook?
In Microsoft Edge, go to Settings > Profiles > Profile preferences. Toggle off the setting that allows single sign-on for Microsoft sites. You should also make sure you are signed out of the Edge browser profile itself on shared computers.
