Why can’t I log back into Microsoft Sway using the Safari browser? Last night I was still able to edit my Sway using Safari on my MacBook?

Dear @SITI MUNIRA,

Thank you for posting your question in the Microsoft Q&A forum.  We understand you're experiencing an issue logging back into Microsoft Sway using the Safari browser on your MacBook, especially since you were able to edit your Sway just last night. This can certainly be frustrating. 

The most common reasons for unexpected login or editing issues in web applications like Sway are related to browser data or settings.

To help me narrow down the cause, could you please provide the following details?  

1. Are you seeing any specific error messages when you try to log in? 
2. Have you recently changed any settings in Safari or updated your macOS? 
3. Can you try logging in from a different network (like a mobile hotspot) to see if the issue replicates? 

In the meantime, please try the following official troubleshooting options which usually resolve issues with basic issues: 

Option 1: Clear browser cache and cookies 

Your browser's stored data might be causing a conflict. Clearing the cache and cookies often resolves login and session-related problems. 

Steps for Safari: 

1. Go to Safari > Preferences (or Settings on newer macOS versions). 
2. Select the Privacy tab. 
3. Click Manage Website Data... and search for and remove any entries related to "microsoft" or "office." 
4. Alternatively, go to Safari > Clear History and select to clear All History.  

Note: This will clear data for all websites. 

Option 2: Check for private browsing/Tracking prevention 

If you are using Private Browsing mode or if your Intelligent Tracking Prevention setting is overly strict, it might block necessary authentication cookies. 

Ensure you are not in Private Browsing mode. In Safari Preferences > Privacy, try temporarily deselecting "Prevent cross-site tracking" to see if that resolves the login issue, then try logging in again. 

Option 3: Update Safari and macOS 

Ensure both your Safari browser and macOS are fully up to date. Updates often include critical security and compatibility fixes that can resolve unexpected issues with web services. 

Check for updates: Go to the Apple menu > System Settings (or System Preferences) > General > Software Update. 

For detailed steps, please refer to these official Mac resources: System Settings on your Mac - Apple Support

Note: Microsoft is providing this information as a convenience to you. The sites are not controlled by Microsoft. Microsoft cannot make any representations regarding the quality, safety, or suitability of any software or information found there. Please make sure that you completely understand the risk before retrieving any suggestions from the above link 

Option 4: Test with a different browser 

As a temporary workaround and to help isolate the issue, please try logging into Sway using a different supported browser, such as Microsoft Edge or Google Chrome, on your MacBook. 

• If it works in another browser: The problem is definitely specific to your Safari settings or installation. 
• If it doesn't work in another browser: The issue might be related to your Microsoft 365 account or network settings, and further investigation will be needed. 

While there is no single document detailing this specific error, Microsoft generally recommends supported browsers and troubleshooting steps for Office Online apps. Sway is fully supported on modern browsers, including Safari. 

For reference on supported browsers and a general starting point for web issues, you can refer to Which browsers work with Microsoft 365 for the web and Microsoft 365 Add-ins - Microsoft Support 

I truly hope you understand that the initial steps I suggested may not have completely resolved the issue, as there might still be underlying causes, we haven't uncovered yet. Please know that I’m here with you every step of the way, ready to work together and do everything I can to help troubleshoot and find the best solution.  

Please let me know if you have any further questions or if the problem persists after trying these solutions. Thank you for your patience and cooperation. 

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